A space time of 3 hours for a flow reactor means that (A) The time required to process one reactor volume of feed (measured at specified conditions) is 3 hours (B) Three reactor volumes of feed can be processed every hour (C) It takes three hours to dump the entire volume of the reactor with feed (D) Conversion is cent per cent after three hours

A space time of 3 hours for a flow reactor means that
(A) The time required to process one reactor volume of feed (measured at
specified conditions) is 3 hours
(B) Three reactor volumes of feed can be processed every hour
(C) It takes three hours to dump the entire volume of the reactor with feed
(D) Conversion is cent per cent after three hours
by

1 Answer

Answer :

(A) The time required to process one reactor volume of feed (measured at
specified conditions) is 3 hours
by

Related questions

A space velocity of 5 hr -1 means that (A) Five reactor volumes of feed (at specified conditions) are being fed into the reactor per hour (B) After every 5 hours, reactor is being filled with the feed (C) Cent per cent conversion can be achieved in at least 5 hours (D) A fixed conversion of a given batch of feed takes 5 hours

Description : A space velocity of 5 hr -1 means that (A) Five reactor volumes of feed (at specified conditions) are being fed into the reactor per hour (B) After every 5 hours, reactor is being filled with the feed ... be achieved in at least 5 hours (D) A fixed conversion of a given batch of feed takes 5 hours

Last Answer : (A) Five reactor volumes of feed (at specified conditions) are being fed into the reactor per hour

Pick out the wrong statement pertaining to space velocity of flow reactors. (A) The unit of space velocity is (time) -1 (B) The space velocity of 3 hr -1 means that three reactor volumes of feed at specified conditions are being fed into the reactor every hour (C) The space velocity of 3 hr -1 means that one third reactor volume of feed at specified conditions are being fed into the reactor (D) None of these

Description : Pick out the wrong statement pertaining to space velocity of flow reactors. (A) The unit of space velocity is (time) -1 (B) The space velocity of 3 hr -1 means that three reactor volumes of ... one third reactor volume of feed at specified conditions are being fed into the reactor (D) None of these

Last Answer : (C) The space velocity of 3 hr -1 means that one third reactor volume of feed at specified conditions are being fed into the reactor

Space velocity (A) Describes the extensive operating characteristics of a tubular flow reactor (B) Is the maximum feed rate per unit volume of reactor for a given conversion (C) Is a measure of the ease of the reaction (D) All (A), (B) and (C)

Description : Space velocity (A) Describes the extensive operating characteristics of a tubular flow reactor (B) Is the maximum feed rate per unit volume of reactor for a given conversion (C) Is a measure of the ease of the reaction (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate or larger amounts of data (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order (D) The ratio of volumes of plug flow reactor to that of mixed reactor is always less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Description : Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate ... less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Last Answer : (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order

With the same reaction time, initial concentration and feed rate, the reaction 2A → B is carried out separately in CSTR and P.F. reactor of equal volumes. The conversion will be (A) Higher in P.F. reactor (B) Higher in CSTR (C) Same in both the reactors (D) Data insufficient; can't be predicted

Description : With the same reaction time, initial concentration and feed rate, the reaction 2A → B is carried out separately in CSTR and P.F. reactor of equal volumes. The conversion will be (A) Higher in P.F. reactor (B) Higher in CSTR (C) Same in both the reactors (D) Data insufficient; can't be predicted

Last Answer : (A) Higher in P.F. reactor

A high space velocity means that a given (A) Reaction can be accomplished with small reactor (B) Conversion can be obtained with a high feed rate (C) Both (A) and (B) (D) None of these

Description : A high space velocity means that a given (A) Reaction can be accomplished with small reactor (B) Conversion can be obtained with a high feed rate (C) Both (A) and (B) (D) None of these

Last Answer : (C) Both (A) and (B)

The ratio of volume of mixed reactor to the volume of P.F.R. (for identical flow rate, feed composition and conversion) for zero order reaction is: (A) ∞(B) 0 (C) 1 (D) > 1

Description : The ratio of volume of mixed reactor to the volume of P.F.R. (for identical flow rate, feed composition and conversion) for zero order reaction is: (A) ∞ (B) 0 (C) 1 (D) > 1

Last Answer : (C) 1

With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion). (A) Increases (B) Decreases (C) Remain same (D) Increases linearly

Description : With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion). (A) Increases (B) Decreases (C) Remain same (D) Increases linearly

Last Answer : (A) Increases

An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP - 0.125CR. A stream containing only P enters the reactor. The residence time required (in hours) for 40% conversion of P is (A) 0.80 (B) 1.33 (C) 1.60 (D) 2.67

Description : An isothermal aqueous phase reversible reaction, P ⇌ R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP - 0.125CR. A stream containing only P enters the reactor. The ... (in hours) for 40% conversion of P is (A) 0.80 (B) 1.33 (C) 1.60 (D) 2.67

Last Answer : (C) 1.60

For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single (A) CSTR of volume V (B) PFR of volume V (C) CSTR of volume V/X (D) PFR of volume V/X

Description : For identical flow rate and feed composition, X plug flow reactors (PER) in series with a total volume V gives the same conversion as single (A) CSTR of volume V (B) PFR of volume V (C) CSTR of volume V/X (D) PFR of volume V/X

Last Answer : (B) PFR of volume V

Mean residence time is equal to the space time, when (A) The feed rate is measured at temperature and pressure in the reactor (B) The temperature, pressure and the density of reaction mixture remains constant throughout the reactor (C) There is no change in number of moles in gaseous reaction (D) All (A), (B) and (C)

Description : Mean residence time is equal to the space time, when (A) The feed rate is measured at temperature and pressure in the reactor (B) The temperature, pressure and the density of reaction mixture remains constant throughout ... no change in number of moles in gaseous reaction (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

The gas phase reaction 2A ⇌ B is carried out in an isothermal plug flow reactor. The feed consists of 80 mole % A and 20 mole % inerts. If the conversion of A at the reactor exit is 50%, then CA/CA0 at the outlet of the reactor is (A) 2/3 (B) 5/8 (C) 1/3 (D) 3/8

Description : The gas phase reaction 2A ⇌ B is carried out in an isothermal plug flow reactor. The feed consists of 80 mole % A and 20 mole % inerts. If the conversion of A at the reactor exit is 50%, then CA/CA0 at the outlet of the reactor is (A) 2/3 (B) 5/8 (C) 1/3 (D) 3/8

Last Answer : (B) 5/8

. A job is budgeted to require 3,300 productive hours after incurring 25% idle time. If the total labour cost budgeted for the job is Rs36,300. What is the labour cost per hour( to the nearest cent)? (a) Rs 8.25 (b) Rs 8.80 (c) Rs 11.00 (d) Rs 14.67

Description : . A job is budgeted to require 3,300 productive hours after incurring 25% idle time. If the total labour  cost budgeted for the job is Rs36,300. What is the labour cost per hour( to the nearest cent)? (a) Rs 8.25 (b) Rs 8.80 (c) Rs 11.00 (d) Rs 14.67

Last Answer : (a) Rs 8.25

A batch reactor is suitable for (A) Achieving cent percent conversion of reactants into products (B) Large scale gaseous phase reactions (C) Liquid phase reactions(D) Obtaining uniform polymerisation products in highly exothermicreactions

Description : A batch reactor is suitable for (A) Achieving cent percent conversion of reactants into products (B) Large scale gaseous phase reactions (C) Liquid phase reactions (D) Obtaining uniform polymerisation products in highly exothermic reactions

Last Answer : (C) Liquid phase reactions

Which of the following fixes the volume of a batch reactor for a particular conversion and production rate? (A) Operating conditions (e.g. pressure and temperature) (B) Rate constant (C) Density of mixture (D) None of these

Description : Which of the following fixes the volume of a batch reactor for a particular conversion and production rate? (A) Operating conditions (e.g. pressure and temperature) (B) Rate constant (C) Density of mixture (D) None of these

Last Answer : (C) Density of mixture

CG Co manufactures a single product T. Budgeted production output of product T during June is 200 units. Each unit of product T requires 6 labour hours for completion and CG Co anticipates 20 per cent idle time. Labour is paid at a rate of Rs7 per hour. The direct labour cost budget for March is (a) Rs 6,720 (b) 8,400 (c) 10,080 (d) 10,500

Description : CG Co manufactures a single product T. Budgeted production output of product T during June is  200 units. Each unit of product T requires 6 labour hours for completion and CG Co anticipates 20 per  cent idle time. Labour is paid at ... for March is (a) Rs 6,720 (b) 8,400 (c) 10,080 (d) 10,500

Last Answer : (d) 10,500

An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will __________ with decrease in space time. (A) Increase (B) Increase exponentially (C) Decrease (D) Remain unchanged

Description : An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will __________ with decrease in space time. (A) Increase (B) Increase exponentially (C) Decrease (D) Remain unchanged

Last Answer : (C) Decrease

N' plug flow reactors in series with a total volume 'V' gives the same conversion as a single plug flow reactor of volume 'V' for __________ order reactions. (A) First (B) Second (C) Third (D) Any

Description : N' plug flow reactors in series with a total volume 'V' gives the same conversion as a single plug flow reactor of volume 'V' for __________ order reactions. (A) First (B) Second (C) Third (D) Any

Last Answer : (D) Any

For series reaction, the relative yield (A) Is always greater for plug-flow reactor than for the single CSTR of the same volume (B) Statement in (A) is wrong (C) Decreases with increasing conversion (D) Both (A) and (C) hold good

Description : For series reaction, the relative yield (A) Is always greater for plug-flow reactor than for the single CSTR of the same volume (B) Statement in (A) is wrong (C) Decreases with increasing conversion (D) Both (A) and (C) hold good

Last Answer : (D) Both (A) and (C) hold good

In flow reactors, the performance equations interrelate the rate of reaction to the (A) Feed rate (B) Reactor volume (C) Extent of reaction (D) All (A), (B) and (C)

Description : In flow reactors, the performance equations interrelate the rate of reaction to the (A) Feed rate (B) Reactor volume (C) Extent of reaction (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a measure of its capacity and is equal to the residence time when the density of reaction mixture is constant (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty (D) In an ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction

Description : Pick out the wrong statement. (A) The vessel dispersion number (D/UL) for plug flow and mixed flow approaches zero and infinity respectively (B) Space time in a flow reactor is a ... ideal tubular flow reactor, mixing takes place in radial direction and there is no mixing in longitudinal direction

Last Answer : (C) Mixed reactor is always smaller than the plug flow reactor for all positive reaction orders for a particular duty

The minimum amount of------------------,irrespective of such private participation,could be specified at a minimum 17.5 per cent of project costs by lending institutions. A. bank loans B. promotors contribution C. fixed capital D. working capital

Description : The minimum amount of------------------,irrespective of such private participation,could be specified at a minimum 17.5 per cent of project costs by lending institutions. A. bank loans B. promotors contribution C. fixed capital D. working capital

Last Answer : B. promotors contribution

Seiko takes pottery classes from two different studios. Paulas pottery charges $18 for clay and charges $10 per hour. Sallys ceramics charges $4 for clay and charges $12 per hour. After how many hours will the studios cost the same?

Description : Seiko takes pottery classes from two different studios. Paulas pottery charges $18 for clay and charges $10 per hour. Sallys ceramics charges $4 for clay and charges $12 per hour. After how many hours will the studios cost the same?

Last Answer : .

An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature. (A) Is always equal to (B) Is always greater than (C) Is always less than (D) May be greater or less than

Description : An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature. (A) Is always equal to (B) Is always greater than (C) Is always less than (D) May be greater or less than

Last Answer : (B) Is always greater than

. A batch reactor is characterised by (A) Constant residence time(B) Variation in extent of reaction and properties of the reaction mixture withtime(C) Variation in reactor volume(D) Very low conversion

Description : . A batch reactor is characterised by (A) Constant residence time (B) Variation in extent of reaction and properties of the reaction mixture with time (C) Variation in reactor volume (D) Very low conversion

Last Answer : (B) Variation in extent of reaction and properties of the reaction mixture with time

On an IQ test consisting of 250 questions, Jasvinder answered 40% of the first 125 questions correctly. What per cent of the other 125 questions does he need to answer correctly for his grade on the entire exam to be 60%? (a) 75% (b) 80% (c) 60% (d) Cannot be determined (e) None of these

Description : On an IQ test consisting of 250 questions, Jasvinder answered 40% of the first 125 questions correctly. What per cent of the other 125 questions does he need to answer correctly for his grade on the entire exam to be 60%? (a) 75% (b) 80% (c) 60% (d) Cannot be determined (e) None of these

Last Answer : (b) 80%

With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will (A) Increase (B) Decrease (C) Remain same (D) Data in insufficient; can't be predicted

Description : With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will (A) Increase (B) Decrease (C) Remain same (D) Data in insufficient; can't be predicted

Last Answer : (A) Increase

A tank is filled by 3 taps K, L and M with uniform flow. The second tap L takes 3 times the time taken by K to fill the tank, while M takes two times the time taken by L to fill the tank. If all the three taps can fill the tank in 14 hours, find the time required by tap K alone to fill the tank. A) 10hrs B) 21hrs C) 14hrs D) 22hrs

Description : A tank is filled by 3 taps K, L and M with uniform flow. The second tap L takes 3 times the time taken by K to fill the tank, while M takes two times the time taken by L to fill the tank. If all ... hours, find the time required by tap K alone to fill the tank. A) 10hrs B) 21hrs C) 14hrs D) 22hrs

Last Answer : B 1/x + 1/ (3x) + (1/6x) = 1/14 9/6x= 1/14 6x/9 = 14 6x=126 X=126/6 X=21

. A first order irreversible reaction, A → B is carried out separately in a constant volume as well as in a variable volume reactor for a particular period. It signifies that __________ in the two reactors. (A) Both conversion as well as concentration are same (B) Conversion in both will be the same but concentrations will be different (C) Both the conversion as well as concentrations will be different (D) None of these

Description : . A first order irreversible reaction, A → B is carried out separately in a constant volume as well as in a variable volume reactor for a particular period. It signifies that __________ in the two ... be different (C) Both the conversion as well as concentrations will be different (D) None of these

Last Answer : (B) Conversion in both will be the same but concentrations will be different

The conversion for a first order liquid phase reaction. A → B in a CSTRis 50%. If another CSTR of the same volume is connected in series, then the % conversion at the exit of the second reactor will be (A) 60 (B) 75 (C) 90 (D) 100

Description : The conversion for a first order liquid phase reaction. A → B in a CSTRis 50%. If another CSTR of the same volume is connected in series, then the % conversion at the exit of the second reactor will be (A) 60 (B) 75 (C) 90 (D) 100

Last Answer : (B) 75

The conversion in a mixed reactor/accomplishing a reaction A → 3R is 50% when gaseous reactant 'A' is introduced at the rate of 1 litre/second and the leaving flow rate is 2 litres/second. The holding time for this operation is __________ second. (A) 0.5 (B) 1 (C) 2(D) 3

Description : The conversion in a mixed reactor/accomplishing a reaction A → 3R is 50% when gaseous reactant 'A' is introduced at the rate of 1 litre/second and the leaving flow rate is 2 litres/second. The holding time for this operation is __________ second. (A) 0.5 (B) 1 (C) 2 (D) 3

Last Answer : (A) 0.5

In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant

Description : In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant

Last Answer : (A) Velocity of reaction can be controlled

For the same residence time, which one will give the maximum conversion? (A) Single stirred tank (v = 5 litres) (B) Two stirred tank (each of 2.5 litres) in series (C) Stirred tank followed by tubular flow reactor (each of 2.5 litres) (D) Single tubular flow reactor (v = 5 litres)

Description : For the same residence time, which one will give the maximum conversion? (A) Single stirred tank (v = 5 litres) (B) Two stirred tank (each of 2.5 litres) in series (C) Stirred tank followed by tubular flow reactor (each of 2.5 litres) (D) Single tubular flow reactor (v = 5 litres)

Last Answer : (D) Single tubular flow reactor (v = 5 litres)

A back mix reactor is (A) Suitable for gas phase reactions (B) Ideal at very low conversion (C) Same as plug flow reactor (PFR) (D) Same as ideal stirred tank reactor

Description : A back mix reactor is (A) Suitable for gas phase reactions (B) Ideal at very low conversion (C) Same as plug flow reactor (PFR) (D) Same as ideal stirred tank reactor

Last Answer : (D) Same as ideal stirred tank reactor

The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit conversion is 20%, then the exit temperature (in k) is (Data: Heat of reaction at 298 K = - 50000 kJ/ kmole of A reacted Heat capacities CPA = CPB = 100kJ/kmole. K (may be assumed to be independent of temperature)) (A) 400 (B) 500 (C) 600 (D) 1000

Description : The reaction A → B is conducted in an adiabatic plug flow reactor (PFR). Pure A at a concentration of 2 kmol/m3 is fed to the reactor at the rate of 0.01 m3 /s and at a temperature of 500 K. If the exit ... /kmole. K (may be assumed to be independent of temperature)) (A) 400 (B) 500 (C) 600 (D) 1000

Last Answer : (C) 600

Which of the following will give maximum gas conversion? (A) Fixed bed reactor (B) Fluidised bed reactor (C) Semi-fluidised bed reactor (D) Plug-flow catalytic reactor

Description : Which of the following will give maximum gas conversion? (A) Fixed bed reactor (B) Fluidised bed reactor (C) Semi-fluidised bed reactor (D) Plug-flow catalytic reactor

Last Answer : (C) Semi-fluidised bed reactor

A control volume refers to what?  a. A fixed region in space  b. A reversible process  c. an isolated system  d. a specified mass

Description : A control volume refers to what?  a. A fixed region in space  b. A reversible process  c. an isolated system  d. a specified mass

Last Answer : A fixed region in space

A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, the downstream 12 miles would then take only one hour less than the upstream 12 miles. What is the speed of the current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Description : A this usual rowing rate, Mohit can travel 12 miles downstream in a certain river in 6 hours less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his 24 miles round trip, ... current in miles per hour? A.2.5m/hr B.4 m/hr C.8/3 m/hr D. 5/3m/hr

Last Answer : Answer-C Basic Formula: Speed of the stream = ½ (a-b) km/hr Explanation: Let the speed in still water be x m/hr Speed of stream be y m/hr Then, speed upstream = x-y m/hr and Speed downstream = x+y m/hr 12/x-y - ... 1] 3y^2 = 8 y so, y = 8/3 speed of the current = 8/3 m/hr = 2 (2/3) m/hr

Pick out the correct statement. (A) A lower temperature favours the reaction of lower activation energy (B) The dispersion number for a reactor/vessel is uL/D (C) The rate controlling step in a reaction involving many steps is the fastest step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

Description : Pick out the correct statement. (A) A lower temperature favours the reaction of lower activation energy (B) The dispersion number for a reactor/vessel is uL/D (C) The rate controlling step in ... step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

Last Answer : (A) A lower temperature favours the reaction of lower activation energy

Processed meat and poultry products have good market. However, their export is mainly hampered due to...... (A) processing not as per demand (B) breeds are not suitable for export (C) no proper transport conditions (D) unhygienic conditions of slaughter houses and animal diseases (E) domestic market is available easily

Description : Processed meat and poultry products have good market. However, their export is mainly hampered due to...... (A) processing not as per demand (B) breeds are not suitable for export ... conditions (D) unhygienic conditions of slaughter houses and animal diseases (E) domestic market is available easily

Last Answer : (D) unhygienic conditions of slaughter houses and animal diseases

In Lurgi coal gasifier, (A) Coking coals cannot be used (B) Low carbon conversion efficiency is achieved (C) Entrainment of solids is higher (D) Larger quantity of coal can be processed

Description : In Lurgi coal gasifier, (A) Coking coals cannot be used (B) Low carbon conversion efficiency is achieved (C) Entrainment of solids is higher (D) Larger quantity of coal can be processed

Last Answer : (D) Larger quantity of coal can be processed

In the Lurgi coal gasifier (A) Coking coals cannot be used (B) Low carbon conversion efficiency is achieved (C) Entrainment of solids is higher (D) Large quantity of coal can be processed

Description : In the Lurgi coal gasifier (A) Coking coals cannot be used (B) Low carbon conversion efficiency is achieved (C) Entrainment of solids is higher (D) Large quantity of coal can be processed

Last Answer : (D) Large quantity of coal can be processed

In a semi-batch reactor, (A) Mixing takes place in axial direction only (B) Velocity of reaction can be controlled (C) Condition similar to plug flow reactor exists (D) Residence time is constant

Description : In a semi-batch reactor, (A) Mixing takes place in axial direction only (B) Velocity of reaction can be controlled (C) Condition similar to plug flow reactor exists (D) Residence time is constant

Last Answer : (B) Velocity of reaction can be controlled

Serial access memories are useful in applications where A) Data consists of numbers B) Short access time is required C) Each stored word is processed differently D) Data naturally needs to flow in and out in serial form

Description : Serial access memories are useful in applications where A) Data consists of numbers B) Short access time is required C) Each stored word is processed differently D) Data naturally needs to flow in and out in serial form

Last Answer : Answer : D

Serial access memories are useful in applications where a. Data consists of numbers b. Short access time is required c. Each stored word is processed differently d. Data naturally needs to flow in and out in a serial form

Description : Serial access memories are useful in applications where a. Data consists of numbers b. Short access time is required c. Each stored word is processed differently d. Data naturally needs to flow in and out in a serial form

Last Answer : d. Data naturally needs to flow in and out in a serial form

Lazy Larry agreed to work on a job for his brother-in-law for thirty hours at eight dollars an hour, on the condition that he would forfeit ten dollars per hour for every hour that he idled. At the end of the thirty hours Larry wasn't owed any money and didn't owe his brother-in-law any money either. How many hours did Larry work and how many hours did he idle? -Riddles

Description : Lazy Larry agreed to work on a job for his brother-in-law for thirty hours at eight dollars an hour, on the condition that he would forfeit ten dollars per hour for every hour that he idled. At the ... -in-law any money either. How many hours did Larry work and how many hours did he idle? -Riddles

Last Answer : Lazy Larry worked 16-2/3 hours and idled 13-1/3 hours. 16-2/3 hours, at $8.00 an hour amounts to the same amount as 13-1/3 hours at $10.00 per hour.

A contractor wishes to determine a suitable combination of manual labour and machine work for the excavation of a multistory construction. For every cum of excavation, 3 man-hours are needed; or 0.2 machine-hour. Costs involved are Rs. 20 per man-hour and Rs. 500 per machine-hour. The total quantity of excavation is estimated to be 4,000 cum. The optimal quantity of excavation to be done manually for minimum total cost will be (a) 1500 cum (b) 1800 cum (c) 2250 cum (d) 2500 cum

Description : A contractor wishes to determine a suitable combination of manual labour and machine work for the excavation of a multistory construction. For every cum of excavation, 3 man-hours are needed; or 0.2 machine-hour. Costs ... total cost will be (a) 1500 cum (b) 1800 cum (c) 2250 cum (d) 2500 cum

Last Answer : (d) 2500 cum

Geetha runs at a speed of 12 km per hour and she increases her speed in every hour by 1 km per hour. In how many hours will he covers 27.8km ? a) 1 1/4 hours b) 2 1/3 hours. c) 3 1/2 hours. d) 2 1/5 hours.

Description : Geetha runs at a speed of 12 km per hour and she increases her speed in every hour by 1 km per hour. In how many hours will he covers 27.8km ? a) 1 1/4 hours b) 2 1/3 hours. c) 3 1/2 hours. d) 2 1/5 hours.

Last Answer : D Geetha starts with 12 kmph. Distance covered in first 1 hour = 12 km she increases her speed in every hour by 1 km. Speed in 2nd hour = 13 km/hr Distance covered in 2nd hour = 13 km Remaining distance = 27.8 ... total time = 1 + 1 + 1/5 hours = 2 1/5 hours. Hence the answer is 2 1/5 hours.