Description : Three pipes, A, B, & C are attached to a tank. A & B can fill it in 20 & 30 minutes respectively while C can empty it in 15 minutes. If A, B & C are kept open successively for 1 minute each, how soon will the tank be filled?
Last Answer : Answer: 167 minutes.
Description : Two taps can fill a bunker in 40 and 48 mins respectively and a waste tap can empty 6 gallons per minute. All the 3 taps working together can fill the bunker in 30 mind. The capacity of the bunker is. A) 480 B) 480 C) 680 D) 780
Last Answer : A Work done by the waste tap in 1 min = 1/30 – (1/40 + 1/48) = 8 – (6+5)/240 = 8-11/240 = -3/240 = -1/80 (negative sign means emptying) Volume of 1/80 part = 60 gallons Volume of whole = (6*80) = 480 gallons
Description : Two pipe P & Q fill a tab in 5 hrs and 20 hrs respectively. If both the pipes are open then due to the leakage, it took 30mins more to fill the tab. If the tab is full, how long will it take for the leakage alone to empty the tank? A) 28 B) 24 C) 36 D) 12
Last Answer : C Part filled by(P+Q) in 1 hr = 1/5 + 1/20 = ¼ So P & Q together can fill the tank in 4 hrs. Work done by the leak in 1 hr = 1 / 4 - 2/9 Leak will empty the tank in 36 hrs.
Description : Pipe A can fill a water tank in 8 hours, Pipe B can fill the same tank in 12 hours and Pipe C can empty the tank in 24 hours. If all three pipes are opened together, in how many hours will the tank be completely filled or empty? a) 4.8 hours b) 5 hours c) 5.4 hours d) 6 hours e) 7.2 hours
Last Answer : If all the three pipes are opened together, in one hour they will fill 1/8 + 1/12 – 1/24 = (3+2-1)/24 = 1/6 part of tank. So, to fill it completely it will take 6 hours. Answer is: d)
Description : Three pumps, M, N and O are opened to fill a tank such that M and N can fill the tank alone in 18 min. and 23 min. respectively and O can empty it in 15 min. After 3 minutes the emptying pipe is closed. In how many minutes the tank will be full in this way? A) 20 B) 25 C) 18 D) 12
Last Answer : D Let the tank full in x minutes, then M and N opened for x minutes and O for 3 minutes. (1/18 + 1/23)*x – (1/15)*3 = 1 (23+18/414)X=1+1/5 Solve, x = 12
Description : Two pipes X and Y can fill a tank in 6 hours and 8 hours respectively while another pipe Z can empty the tank in 4.8 hours. If all the three pipes are
Last Answer : Two pipes X and Y can fill a tank in 6 hours and 8 hours respectively while another pipe Z can ... then the time in which the tank can be filled.
Description : Three pipes P, Q and R can fill a tank from empty to full in 40 minutes, 15 minutes, and 30 minutes respectively. When the tank is empty, all the three pipes are opened. P, Q and R discharge chemical solutions X, Y and Z respectively. ... 5 minutes? a) 8 / 15 b) 7 / 15 c) 8 / 17 d) 6 / 13 e) 8 / 13
Last Answer : a Part of the tank filled by pipe P in 1 minute = 1 / 40 Part of the tank filled by pipe Q in 1 minute = 1 / 15 Part of the tank filled by pipe R in 1 minute = 1/ 30 Here we have to find the proportion of ... together in 5 minute = 5 1/8 = 5/ 8 Required proportion = (1/3) / ( 5/8) = 8 / 15
Description : Two pipes P and Q can fill a cistern in 15 minutes and 20 minutes respectively. Both are opened together, but at the end of 5 minutes, the pipe P is t
Last Answer : Two pipes P and Q can fill a cistern in 15 minutes and 20 minutes respectively. Both are opened ... will the pipe Q take to fill the cistern ?
Description : A tank is 1/4th full. Two pipes which fill the tank in 30minutes and 40 minutes respectively are opened simultaneously. After 10 minutes, a third pipe which empties the full tank in 60 minutes is also opened. In how many minutes the tank will be full? A) 14 B) 12 C) 15 D) 17
Last Answer : A Since 1/4th is already filled, 3/4th is to filled now. (1/30 + 1/40)*(10+x) – (1/60)*x = ¾ 7/120(10+x)-x/60=3/4 7x-2x/120=3/4-7/12 5x/120=1/6 30x=120 X=4 So total 10+4=14minutes
Description : Two pipes, Xand Y can fill a tank in 36 and 30 minutes respectively. Both are opened together, but at the end of 3minutes, X is turned off. In how many more minutes will Y fill the cistern? A) 7(24/5) B) 7(1/2) C) 24(1/3) D) 8(1/4)
Last Answer : C X can fill cistern in 36 minutes. X fills cistern in 1 minute = 1/36 Y can fill cistern in 30 minutes. Y fills cistern in 1 minute = 1/30 part. Xand Y together can fill cistern in 1 minute, = {(1/ ... part. 147/180 part cistern must be filled by Y in, [(147/180)/(1/30)] = 24(1/3) minutes.
Description : Faucet A basically used as inlet pipe and Faucet B is used as outlet pipe. Faucet A and B both are opened simultaneously, all the time. When Faucet A fills the tank and Faucet B empty the tank, it will take thrice the ... efficiency of Faucet A and Faucet B respectively? a) 1:2 b) 2:1 c) 1:3 d) 3:1
Last Answer : B Efficiency when both pipes used to fill = A + B And efficiency when Faucet A is used to fill and Faucet B is used to empty the tank = A-B So (A+B)/(A-B)=3/1 A/B+1/(A/B-1)=3/1 A/B+1=3(A/B-1) 3A/B-A/B=4 2A/B=4 A/B=2 Thus, the ratio of efficiency of Faucet A and B =2:1
Description : Pipe A can fill an empty tank in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins. If all of them work together, find the time taken to fill the tank? (a) 17 1/7 mins (b) 20 mins (c) 8 mins (d) none of these
Last Answer : (a) 17 1/7 mins
Description : Two filling tap can fill a dumper in 14 and 28 min. respectively and when the waste tap is open, they can together fill it in 35 min. The waste pipe can empty the full dumper in – A) 152/9 hrs. B) 137/7 hrs. C) 60/9 hrs. D) 140/11 hrs.
Last Answer : D 1/14 + 1/28 – 1/35 =>10 + 5 – 4/140 =>11/140 =>140/11 => hence answer is 140/11 hours.
Description : Two pipes A and B can fill a tank in 5 and 6hrs.Pipe C can empty it in 12hrs.If all the 3 pipes are opened together,then the tank will be filled in 1)1(13/17)hrs 2)2(8/11)hours. 3)3(9/17)hrs 4)4(1/2)hrs
Last Answer : 3)3(9/17)hrs Exp:Net part filled in 1hr=>(1/5+1/6-1/12)=17/60 Tank filled in=60/17=3(9/17).
Description : A cistern is filled in 15 hours by three pipes P, Q and R. The pipe R is thrice as fast as Q and Q is thrice as fast as P. How much time will pipe P alone take to fill the tank? A) 120 hrs B) 195 hrs C) 135 hrs D) Cannot be determined
Last Answer : B Suppose pipe P alone takes x hours to fill the tank. Then, pipes Q and R will take x/3 and x/9hours respectively to fill the tank. 1/x + 3/x + 9/x = 1/15 13/x = 1/15 => x = 195 hrs.
Description : A large cistern can be filled by 2 pipes P & Q in 120 mins and 80 mins respectively. How many mins will it take to fill the cistern from empty state if Q is used for half the time and P & Q fil it together for the other half? A) 2hrs B) 1hr C) 3hrs D) 4hrs
Last Answer : B Part filled by (P+Q) in 1 min = 1/120 + 1/80 =2+3/240 = 5/240 = 1/48 Suppose the cistern is filled in x mins then, x/2 (1/48 + 1/80) = 1 x/2(5+3/240)=1 8x/480 = 1 x=480/8 x= 60 mins or 1 hr
Description : Two taps M and N can alone fill a tank in 80 minutes and 120 minutes respectively. But due to a leakage of tank, it took 12 more minutes to fill the tank. In how many hours, the leak can alone empty the full tank? A) 240 B) 230 C) 248 D) 256
Last Answer : A A and B can fill tank in (1/80 + 1/120) = 1/48 so 48minutes But it took 12 more minutes, this means the tank got full in 48+12= 60 minutes So (1/80 + 1/120 – 1/x) = 1/60 1/X=1/80+1/120-1/60 Solve, x = 240
Description : A pipe can fill a tank in 4 hours and another pipe can empty the same tank in 6 hours. When both the pipes are opened simultaneously, the part of tank
Last Answer : A pipe can fill a tank in 4 hours and another pipe can empty the same tank in 6 hours. When both the ... the part of tank filled in 1 hour is ..
Description : Two taps P and Q can separately fill a tank in 120mins and 150 mins respectively. There is a 3rd tap in the bottom of the tank to empty it. If all of the 3 taps are simultaneously opened, then the tank is full ... . In how much time the 3rd pipe alone can empty the tank? A) 100 B) 200 C) 300 D) 400
Last Answer : B Work done by the 3 tap in 1 min = 1/100 – ( 1/120 + 1/150) = 1/100 – (5+4/600) =1/100 – 9/600 =6-9/600 = - 3/600 = - 1/200(negative signs mean empting) Therefore the 3rd tap alone can empty the tank in 200 mins
Description : Two pumps P & Q can fill a tank in 12 mins and 15 mins respectively while a third pipe R can empty the full tank in 6 mins. P & Q kept open for 5 mins in the beginning and then R is also opened. In what time is tank emptied? A) 30mins B) 35mins C) 40mins D) 45 mins
Last Answer : D Part filled in 5 min = 5(1/12 +1/15) = 5*9/60 = ¾ Part emptied in 1 min when all the pumps are opened, = 1/6 – (1/12 + 1/15) = 1/6 – 3/20 = 1/60 Now 1/60 is part emptied in 1 min Therefore ¾ part will be emptied in 60 * ¾ = 45 mins
Description : On Ashok marg, three consecutive traffic lights change after 36, 42 and 72 seconds respectively. If the lights are switched on at 9.00 A.M sharp, at what time will they change simultaneously? a) 9 :08 :44 b) 9:08:24 c) 9:08:04 d) 9:08:34
Last Answer : b) 9:08:24
Description : Pipes P, Q and R which fill the tank together in 12 hours are opened for 2hours after which pipe R was closed. Find the number of hours taken by pipe R to fill the tank if the remaining tank is filled in 14 hours. A) 16 B) 14 C) 20 D) 42
Last Answer : D 1/P + 1/Q + 1/R = 1/12 Now given that first all open for 2hours, then R closed and P+Q completes in 14 hours, so (1/P + 1/Q + 1/R) *2 + (1/P + 1/Q)*14 = 1 Put 1/P + 1/Q = 1/12 – 1/R (1/12 – 1/R + 1/R) *2 + (1/12 – 1/R)*14 = 1 1/6+ 14/12 – 14/R = 1 Solve, R = 42
Description : A can do a work in 15 days and B in 20 days. If they work together for 4 days, then the fraction of work that is left is a) 7/15 b) 8/10 c) 8/15 d) 7/20
Last Answer : c) 8/15
Description : Three pipes A, B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is: a) 10 b) 14 c) 12 d) 13 e) 15
Last Answer : (A+B+C) - (A+B) (A+B+C) =1/6 and (A+B+C) in 2hrs=2/6 and remaining part 1-2/6=2/3. So (A+B) in 7 hrs is 2/ (3*7) =2/21. 1/6-2/21=1/14 so answer is 14. Answer: b)
Description : A tank has two inlet pipes, A and B, which can fill the tank in 12 hours and 18 hours respectively, and an outlet C which can empty the tank in 9 hour
Last Answer : A tank has two inlet pipes, A and B, which can fill the tank in 12 hours and 18 hours ... time taken right from the start to fill the tank.
Description : Pipe A usually fills a tank in 2 hours. On account of a leak at the bottom of the tank, it takes pipe A 30 more minutes to fill the tank. How long will the leak take to empty a full tank if pipe A is shut? a) 4 hours b) 3 hours c) 6 hours d) 8 hours e) 10 hours
Last Answer : portion of the tank filled by the pipe A in 1 hour = ½ of the tank let the portion of the tank emptied because of the leak in 1 hour be 1/x of the tank therefore, in 1 hour , portion of the tank filled = 1/2 - 1 ... 1/2 - 1/x = 1/2.5 or x = 10 hence, it takes 10 hours to empty a full tank Answer: e)
Description : What is the greatest 6-digit number that is divisible by 15, 24 and 28? a) 999650 b)999600 c)999825 d)999570
Last Answer : b)999600
Description : A tank can be filled by a tap in 6 hours and emptied by an outlet pipe in 8 hours. How long will it take to fill the cistern if both the taps are opened together? 1. 24 hours 2. 22 hours 3. 21 hours 4. 18 hours 5. 20 hours
Last Answer : 1;
Description : Two pipes fills a tank in 12 hours and 15 hours respectively while a third pipe empties the tank in 18 hours. !f all three pipes operate simultaneously, in what time will the tank be full? a) 10 hours b) 10 10/17 hours c) 11 hours d) 9 hours e) 12 1/17 hours
Last Answer : b) 10 10/17 hours
Description : Faucet A and B can fill a tank in 15 and 9 hrs respectively. Faucet C can empty it in 45 h. The tank is half full. All the three faucets are in operation simultaneously. After how much time the tank will be full ? A) 1(7/15)hrs B) 2(1/11)hrs C) 3(3/14)hrs D) 3(3/11)hrs
Last Answer : C In 1 hr = 1/15+1/9 – 1/45 =>3+5-1/45 = 7/45 ½ tank filled by 3 Faucets = 45/7*1/2 => 45/14 =>3(3/14)
Description : Bucket A has twice the capacity as bucket B. It takes 120 turns for bucket A to fill the empty dumper. How many turns it will take for both the buckets A and B, having each turn together to fill the empty dumper. A) 40 B) 50 C) 70 D) 80
Last Answer : D Let capacity of A be x litres Then capacity of B = x/2 litres Capacity of the dumper = 120x litres Required number of turns = 120x/ x =x/2 = 2 (120x)/3x =2430x/3x =80.
Description : A cylindrical drum of 15cm radius and 70cm height is full of water. The water is emptied into a rectangular tank 225cm long and 70cm wide. Find the height of water level in the tank. a) 3.5cm b) 2.25cm c) 3.142cm d) 1.57cm
Last Answer : c) 3.142cm
Description : Two faucet can separately fill a cistern 30minutes and 45 minutes respectively and when the waste faucet is open, they can together fill it in 54 minutes. The waste faucet can empty the full cistern in? A) 27 min B) 23 min C) 23 min D) 29 min
Last Answer : A 1/30 + 1/45 - 1/x = 1/54 1/x=1/30+1/45-1/54 1/x=9+6-5/270 1/x=10/270 1/x=1/27 x = 27
Description : Twenty workers can complete a piece of work in 30 days. After how many days should 5 workers leave the job so that the work is completed in 35 days? a) 5 days b) 10 days c) 15 days d) 20 days
Last Answer : c) 15 days
Description : The cost of preparing a cricket ground of rectangular shape at 70 paisa per square meter is Rs.508.20. Find the perimeter of the field if its sides are in the ratio 3:2 a) 121m b) 96m c) 55m d) 110m
Last Answer : d) 110m
Description : A tank has two faucet which fill it in 15 mins and 18 mins respectively. There is also a waste faucet in the tank. When all the 3 are opened the empty tank is full in 25 mins. How long the waste faucet take to empty the full tank? A) 450/17 mins B) 450/28 mins C) 450/37 mins D) 450/22 mins
Last Answer : C Work done by the waste faucet in 1 minute =>1/25 – (1/15 + 1/18) =>1/25 – (6+5/90) = 1/25 – 11/90 => - 37/450 Here negative sign means emptying Therefore waste faucet will empty the full tank in 450/37 mins.
Description : An anti-air craft gun can take a maximum of four shots at an enemy plane moving away from it. The probability of hitting the plane at the first, second, third and fourth shots are 0.4, 0.3, 0.2 and 0.1 ... is hit when all the four shots are fired? a) 0.6872 b) 0.4379 c) 0.6976 d) 0.3452
Last Answer : c) 0.6976
Description : The external length, breadth and height of a closed box are 10cm, 9cm and 7cm respectively. The total inner surface area of the box is 262 sq.cm. If the walls of the box are of uniform thickness “t” cm, then “t” equals a) 1cm b) 23/3 cm c) 28/9 cm d) 42.5 cm
Last Answer : a) 1cm
Description : Taps P, Q and R can fill a tank in 3, 4 and 5 hours respectively. If all the taps are opened together and after 30 minutes taps Q and R are turned off, find the total time in which the tank is full. A) 2(3/8)hrs B) 1(1/7)hrs C) 2(13/40)hrs D) 3(13/43)hrs
Last Answer : C In 1 hr P, Q, R = 1/3+1/4+1/5 = 20+15+12/60 = 47/60 Filled in 30m = 47/120 Remaining = 1-47/120 =73/120 Tap P = 3*73/120= 219/120 Total = 219/120+1/2 =219+60 /120= 279/120= 2 13/40 hrs
Description : Two faucet P and Q can fill a tank in 10 min. and 20 min. respectively. A water faucet R can empty the tank in 10 min. First P and Q are opened. After 3 min, R is also opened. In how much time, the tank is full? A) 17m B) 15m C) 11m D) 19m
Last Answer : C Part filled in 3 min. = 3*((1/10)+(1/20)) = 3 * (2+1/20) =>3(3/20) = 9/20 Remaining part=(1-(9/20))=(11/20). Net part filled in 1min. when P,Q and R are opened=(1/10)+(1/ ... (1/20). Now,(1/20) part is filled in one minute. (11/20) part is filled in = (20*(11/20))=11minutes.
Description : How many numbers greater than 400 can be formed with digits 3,4,8,9 with no digits being repeated? a) 24 b) 18 c) 42 d) 45
Last Answer : c) 42
Description : Two taps A and B are opened together to fill a tank. Both the taps fill the tank in time x If B separately took 25 minutes more time than x to fill the tank and B took 49 minutes more time than x ... the tank, then find out the value of x? A) 48 minutes B) 24 minutes C) 54 minutes D) 35 minutes
Last Answer : D Time is taken to fill the tank by both taps x = √a*b x = √25*49 => 5*7 => 35
Description : The min and max size permissible for folded aerogramme is a) 100 X 140 & 120 X 120 b) 90 X 140 & 110 X 120 c) 80 X 140 & 100 X 120 d) None of the above
Last Answer : b) 90 X 140 & 110 X 120
Description : The subcritical steam generators operate between a pressure ranges of? (rra) 120-160 bar (rrb) 100-110 bar ( c) 130-180 bar (rrd) 140- 200 bar
Last Answer : ( c) 130-180 bar
Description : Two trains 240m and 170m in length are running towards each other on parallel tracks. One train has a speed of 51kmph and the other has a speed of 45kmph. In what time after the meet first will they be clear of each other? a) 6.714s b) 12.2 s c) 15.375s d) 16s
Last Answer : c) 15.375s
Description : I bought 15 pens and sold 12 of them at the cost price of 18 pens. What is the profit percentage? a) 50 b) 25 c) 30 d) 45
Last Answer : a) 50
Description : A pipe can fill the tank in 12 hours.Because of a leak in the tank it took 16(1/2) hours to fill the tank.If the tank is full,how much time will the leak take to empty it? A) 18hrs51mins B) 18hrs 20min C) 18hrs 40min D) 18hrs 45min E) None of these
Last Answer : A =>1/12-2/33 = 11-4/132. ==>7/132 =>132/7 hrs =>132/7 hrs=>1131 mins =>18hrs 51min
Description : A trader mixes Ariel detergent costing Rs. 64 per kg with “Surf excel” which costs Rs. 76per kg in the ratio 1:3. If the cost of Surf excel drops to Rs.74 per kg, then in what ratio should he mix the two to leave the cost of mixture unchanged? a) 1:9 b) 1:8 c) 9:1 d) 8:1
Last Answer : a) 1:9
Description : One tap can fill a tank thrice as fast as another tap. If together the two taps can fill the tank in 12 minutes, then the slower tap alone will be able to fill the tank in A) 30min B) 33min C) 32min D) 35min
Last Answer : C (1/x)+(1/3x)=(1/12) 3+1/3x = 4/3x = 1/12 3x = 48 x=32mins
Description : Find the number of divisors of 2475 that are not perfect squares? a) 14 b) 16 c) 20 d) 10
Last Answer : a) 14