The average age of the students in a class is 14. The average age of half of the students in that class and the class teacher is 16. The average age of the remaining half of the students is 15. What is the number of students in that class? a) 20 b) 70 c) 80 d) Cannot be determined e) None of these

1 Answer

Answer :

Because total no. of students is not known we cannot find the answer. Answer: d)

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Description : The average age of 30 students in a class is 12 years. The average age of a group of 5 of the students is 10 years and that of another group of 5 of them is 14 years. The average of the remaining students is : a) 8 years b) 10 years c) 12 years d) 14 years e) 15 years

Last Answer : Let it be x . Then : 5×10+5×14+20×x=30×12 20x=360-120 or 20x=240 or x = 12 Answer: c)

Description : The average age of 30 boys of a class is equal to 14 years. When the age of the class teacher is included the average becomes 15 years. Find the age of the class teacher? A.50 B.44 C.45 D.42 E.None of these

Last Answer : Answer – C (45) Explanation – Total ages of 30 boys = 14 x 30 = 420 years Total age when class teacher is included = 15 x 31 = 465 years Age of class teacher = 465 – 420 = 45 years

Description : The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is: A. 1 : 4 B. 2 : 3 C. 3 : 4 D. 4 : 2 E. None of these

Last Answer : Answer – B (2 : 3) Explanation – Let the ratio be k:1 Then, k x 16.4 + 1 x 15.4 = (k + 1) x 15.8 (16.4 – 15.8) k = (15.8 – 15.4) k=2/3

Description : Rubesh generally takes 80 minutes to reach home from office. Due to rain, he travelled at 2/3rd of his usual speed for the 1st half of the distance. At what speed should rubesh travel the remaining distance ... c) 2.5 times the original speed d) 3 times the original speed e) Cannot reach on time

Last Answer : Under the normal speed, 40 minutes for half the distance Due to rain, time taken will be 40 / (2/3) = 40 × (3/2) = 60 minutes So, in 20 minutes he has to cover the distance he usually covers in 40 minutes. So, he has to travel at twice the original speed. Answer: b)

Description : What least number would be subtracted from 427398 so that the remaining number is divisible by 15? 1. 13 2. 3 3. 16 4. 11 5. 14

Last Answer : Answer- 2 ( 3) Explanation:- On dividing 427398 by 15 we get the remainder 3, so 3 should be subtracted 

Description : If the price of Mango is Rs. 130 per kg, Apple is Rs. 140 per kg and Orange is Rs. 80 per kg, then what is the ratio of their cost at vendor A? 1) 11 : 14 : 16 2) 39 : 28: 20 3) 39 : 28 : 21 4) 15 : 14 : 11 5) 39 : 26 : 20

Last Answer : 2) 39 : 28: 20

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 : The average price of 10 books is Rs. 12 while the average price of 8 of these books is Rs. 11.75. Of the remaining two books, if the price of one book is 60% more than the price of the other, what is the price of ... and Rs 16 B.Rs 12 and Rs 24 C.Rs 24 and Rs 18 D.Rs 28 and Rs 12 E.None of these

Last Answer : Answer - A (Rs 10 and Rs 16) Explanation - Total price of the two books = Rs. [(12 x 10) - (11.75 x 8)] = Rs. (120 - 94) = Rs. 26 Let the price of one book be Rs.x Then, the price of other book = Rs. (x ... /5)x= (8/5)x so, x +(8/5)x=26 , x=10 The prices of the two books are Rs. 10 and Rs. 16

Description : The price of two dozens of oranges is Rs.120/-more than the price of one kg. of mango. The price of one dozen of apple is Rs.80/- more than the price of one kg of mango. Which of the following represents the ... apple respectively? a) 4 : 5 b) 3 : 2 c) 7 : 9 d) Cannot be determined e) None of these

Last Answer : Because no. of mangoes is unknown. So ratio cannot be calculated. Answer: d)

Description : Reshma purchased 120 chairs at price of Rs. 110 per chair. He sold 30 chairsat a profit of Rs. 12 per chair and 75 chairs at profit of Rs. 14 per chairs. The remaining chairs were sold at a loss of Rs. 7 per chairs ... the average profit per table? A. Rs 10.56 B. Rs 10.87 C. Rs 12.123 D. Rs 12.67 

Last Answer : Answer – B (Rs 10.875) Explanation – Total C.P = Rs. (120 x 110) =Rs. 13200. Total S.P = Rs.[(30 x 110 + 30 x 12) + (75 x 110 + 75 x 14) + (15 x 110 – 15 x 7) =Rs..14505 Average profit = Rs. (14505 – 13200) /120 = Rs. 1305/120= 10.875

Description : Madhan was 3 times as old as his daughter 10 years ago. After 10 years, Madhan will be twice as old as his daughter. Find out the present age of Madhan. a) 68 years b) 70 years c) 40 years d) 55 years e) 80 years

Last Answer : b Let age of the daughter before 10 years = x Then, age of Madhan before 10 years = 3x After 10 years, Madhan will be twice as old as his daughter. ⇒ 3x + 20 = 2( x+20) ⇒ x = 20 ⇒ Present age of Madhan = 3x + 10 = 3× 20+ 10 = 70 years.

Description : The average of weight of three men A,B and C is 84 kg. Another man D joins the group and the average now becomes 80 kg. If another man E, whose weight is 3 kg.more than that of D, replaces A, then the average weight of B,C ... 79 kg. The weight of A is : a) 70 kg b) 72 kg c) 75 kg d) 80 kg e) 78 kg

Last Answer : A+B+C = 3×84=252 A+B+C+D= (4×80)=320 D = (320-252)=68 and E = (68+3)=71 Now, B+C+D+E = (4×79)=316 B+C+D=(316-71)=245 kg So, A = (320-245)=75 kg Answer: c)

Description : 24 14 26 ? 28 16 30 a) 13 b) 17 c) 15 d) 11 e) 20

Last Answer : The series consists of two series 1 and 2: Series 1 : 24 26 28 30 +2 +2 +2 Series 2 : 14 15 16 +1 +1 Answer: c)

Description : Prasad and Satish started a business with investments of Rs.2000 and Rs.5300 respectively. At the end of every month, Prasad invests Rs.300 while Satish withdraws Rs.300. What is the ratio in which they should share the profits at the end of one year. a)13:14 b)1:1 c)14:13 d)Cannot be determined

Last Answer : b)1:1

Description : A vendor bought 30 dozen bananas at Rs.16 per dozen. He sold 10 dozens at Rs.20 per dozen and 16 dozens at Rs.25 per dozen. The remaining 4 dozens were rotten and he threw away. Find his profit percentage. a)20% b)25% c)30% d)33 1/3%

Last Answer : b)25%

Description : The mean marks obtained by a class of 40 students is 65. The mean marks of half of the students is found to be 45. The mean marks of the remaining students is (A) 85 (B) 60 (C) 70 (D) 65

Last Answer : Answer: A

Description : The average weight of a group of 75 women was calculated as 47 kg. It was later discovered that the weight of one of the women was read as 45 kg, whereas her actual weight was 25kg. What is the actual average weight ... kg (b) 46.64 kg (c) 45.96 kg (d) Cannot be determined (e) None of these

Last Answer : (a) 46.73 kg

Description : If the compound interest accrued on an amount of Rs.15,000/- in two years is Rs.2,496/-.What is the rate of interest p.c.p.a.? a) 8 b) 12 c) 7.5 d) Cannot be determined e) None of these

Last Answer : Let the rate of interest p.c.p.a. be x. 2496 =15000 * x /100 x = 16.64 16.64 is the rate of interest compounded for two year & for one year = 8% 8% C.I. table for two year. I year = 8% II year = 8.64 Total =16.64% Answer: a)

Description : The average age of the whole class is 12.05 years. The average age of all girls is 12.5 years and the average age of boys is 11.75 years. If the total number of boys is 45 then what is the total number of girls in the class? a) 20 b) 25 c) 30 d) 35 e) 40

Last Answer : Let the number of girls be x. The number of boys is 45. :. Total age of boys and girls in the class = (x+45) × 12.05 or, (x+45) × 12.05 = 45 × 11.75 + x × 12.5 or, 12.05x + 542.25 = 528.75 + 12.5x or, 13.5 = 0.45x or, x = 13.5/0.45 = 30 Answer is: c)

Description : Hemant sold 10 sarees for a total profit of Rs. 460 and 12 sarees for a total profit of Rs. 144. At what profit per saree should he sell the remaining 20 sarees so that he gets an average profit of Rs. 18 per sarees? A. Rs 7.10 B. Rs 7.60 C. Rs 7.99 D. Rs 8

Last Answer : Answer – B (Rs 7.60) Explanation – Total profit required = Rs.(42 x 18) = Rs.756 Profit on 22 sarees = Rs. (460 + 144) = Rs. 604 Profit on 20 sarees = Rs. (756 – 604) = Rs. 152 Average profit on these sarees = Rs.(152/20) = Rs. 7.60

Description : The average age of two persons is 46 years. 16 years back the ratio between their ages were 1 : 2, then what is the difference between present ages of these two persons? 1) 16 years 2) 20 years 3) 24 years 4) 12 years 5) 8 years

Last Answer : 2) 20 years

Description :  on analyzing the result of an competitive exam the teacher found that the average for the entire the class was 69 marks. If we say that average of 10 % of the students scored 77 marks and average of 28 % of the ... marks of the remaining students of the class A) 67.54 B) 68.26 C) 66.91 D) 69.06 

Last Answer : D) average of entire class = 69marks average of 28 % of the students = 66 marks average of 10% of the students = 77 marks then % of remaining students = (100- 10 - 28) = 62% let the average of 62% of the ... (62*x)+770+1848= 6900 62 * x = 6900-770-1848 62*x = 4282 x = 69.06

Description : 10 years ago the average age of all the 25 teachers of a college was 45 years. 4 years ago, a teacher retired from the post at the age of 60 years, and was replaced by a new teacher whose age was 54 years. ... 53 b) Between 53 and 54 c) Between 54 and 55 d) Between 55 and 56 e) None of the above

Last Answer : Let current year be 2015 In 2005, sum of all ages = 25 45 = 1125 In 2015, sum of all ages = 1125 + (25 10) = 1375 Now 60 year old teacher was replaced by a 54 year old teacher. So we need ... all ages in 2015 considering the replacement teacher = 1375 - 6 = 1369 Average = 1369/25 = 54.76 Answer: c)

Description : A is 2 years older than B who is twice as old as C. If sum of ages of A, B and C is 37 years, find the age of A. a) 7 years b) 9 years c) 14 years d) 16 years e) None of these

Last Answer : Let the age of C be x years. Then age of B = 2x and age of A = 2x + 2 sum of ages of A, B and C = (2x + 2) + (2x) + x = 37 (5x + 2) = 37  x = 7 Age of A = 2x + 2 = 16 years Answer: d)

Description : One year ago the ratio between Sam and Ash’s age was 4:3. One year hence the ratio of their ages will be 5:4. What is the sum of their present ages in years? A.14 B.16 C.18 D.12 E.None of these

Last Answer : Answer - B (16) Explanation - Let one year ago Sam's age be 4X years And, Ash's age be 3X years Present age of Sam = (4X + 1) years Present age of Ash= (3X + 1) years One year hence Sam's age = (4X + 2) ... = 2 Sum of their present ages = 4X + 1 + 3X + 1 = 7X + 2 = 7 x 2 + 2 = 16 years.

Description : 3 ? 113 673 3361 13441 40321 a) 13 b) 14 c) 15 d) 16 e) 17

Last Answer : The series is: 3 × 8 – 7 = 17; 17 × 7 – 6 = 113; 113 × 6 – 5 = 673; 673 × 5 – 4 = 3361; 3361 × 4 – 3 = 13441; 13441 × 3 – 2 = 40321 Answer: e)

Description : Present ages of A and B are 50 years and 18 years respectively. In how many years will A be twice as old as B? a) 14 years b) 15 years c) 16 years d) 18 years e) None of these

Last Answer : Let the required time be x years. then (50+x) = 2 (18 + x) = 50 + x = 36 + 2x  x = 14 years. Alternative method : Double of B’s age = 2 × 18 = 36 years difference between A’s present age and double of B’s age = 50 – 36= 14 years. A will be twice of B’s age after 14 years. Answer: a)

Description : What is the average score in an exam taken by 500 students where the minimum score is 200? a. Half the students scored above 700. b. Half the students scored below 700. c. The maximum score in the ... . e) If the data in statement a, b and c together are not sufficient to answer the question.

Last Answer : The fact that half scored above 700, and other half less than 700 does not tell the actual distribution of scores to calculate the average. Statement (c) also does not help us determine the average. Answer: e)

Description : In a class there are 15 boys and 10 girls. Three students are selected at random. The difference between the probability that 2 boys and 1 girl are selected compared to 1 boy and 2 girls are selected is: a) 23/78 b) 19/88 c) 15/92 d) 4/23 e) 7/46

Last Answer : 2 boys, 1 gi(Prl = (15c2×10c1) / 25c3 = 1050/2300 1 boy, 2 girls = (15c1×10c2) / 25c3 = 675/2300 Difference = (1050 - 675)/2300 = 375/2300 = 15/92 Answer: c)

Description : If the positions of the digits of a two digit number are interchanged, the number obtained is smaller than the original number by 27. If the digits of the number are in the ratio of 1 : 2, what is the original number ? a) 25 b) 81 c) 36 d) Cannot be determined e) None of these

Last Answer : Cannot be determined Answer: d)

Description : The average age of 150 students in a class is 40% of the number of students in the class and the average age of a group of 50 students present in the class is 32yrs and the average age of another 50 students ... is the average age of the remaining students in the class? A) 102 B) 118 C) 112 D) 108

Last Answer : C) 150 students average 150×40/100=60 years According to the question, 150×60=50×32+50×36+50×X 50×X=9000-1600-1800 50x=5600 X=112

Description : In a bag there arc coins of 25 paise and 10 paise in the ratio of 6 : 17. If the bag contains Rs. 16 then the number of 10-paise coins is a) 30 b) 40 c) 70 d) 85 e) 65

Last Answer : d) 85

Description : Sush was thrice as old as Poonam 6 years back. Sush will be 5/3 times as old as Poonam 6 years hence. How old is Poonam today? A.20 B.14 C.12 D.15 E.None of these

Last Answer : Answer – C (12) Explanation – Let Poonam age 6 years back = x. Then, Sush age 6 years back = 3x. (5/3) * (X + 6 + 6) = (3X + 6 + 6) So 5(x+ 12) = 3(3x+ 12), so x=6. Poonam Age = (x+ 6) years = 12 years

Description : An amount becomes 160% of itself in 5 years through simple interest. At the same rate of interest, how long will it take for the amount to more than double itself if we use compound interest? a) 7 b) 8 c) 9 d) 10 e) cannot be determined

Last Answer : Answer: a)

Description : In racing over a given distance, A can beat B by 20m, B can beat C by 10m, A can beat C by 28m. The racing distance is? a) 58 m b) 116 m c) 100 m d) 120 m e) cannot be determined

Last Answer : Let the uniform speeds of A,B,C be vA,vB,vC, respectively. Let t1 be the time taken for the race between A and B and t2 be the time taken for race between B and C Since A covers the distance in time t1, race between A and C ... ) = VB/ VC = d/(d-10) Thus (d-20)(d-10)=d(d-28).Hence, d=100. Answer: c)

Description : If the numerator of a fraction is increased by 25% and the denominator is doubled, the fraction thus obtained is 5/9. What is the original fraction? a) 3/4 b) 7/8 c) 8/9 d) Cannot be determined e) None of these

Last Answer : Let the numerator & denominator of a fraction be n & d. According to questions, = n × 5 / d × 8 = 5/9 = n/d = 8 × 5 / 5 × 9 = n/d = 8/9 Answer: c)

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%

Description : Find the number which when multiplied by 13 is increased by 180: 1. 20 2. 15 3. 12 4. 5 5. 14

Last Answer : Answer- 2 (15) Explanation:- let no. be X X *13= X+180 !2x=180 x=15

Description : The average age of three -seventh of class is 49, what should be the average of remaining four-seventh students so that the average of the entire class is 63? A) 24.5 B) 86.5 C) 73.5 D) 25.5

Last Answer : C) According to the question, 63=3/7×49+4/7×y 63=147/7+4y/7 441=147+4y 4y=294 Y=73.5

Description : The Cricketer average score in 40 over is 21, if the man scores 23runs in 8over, 26 runs in 10 over and 18runs in 14 over. What is the average score in remaining over? A) 18 B) 19 C) 16 D) 20 

Last Answer : A) According to the question 40*21=23*8+26*10+18*14+8×X 840=184+260+252+8x 8x=144  X=144/8=18 runs

Description : A shopkeeper declares that he sells rice at the cost price. However he uses a weight of 425 grams. Instead of 500 grams, what is his percentage of profit? a) a) 16 5/6 b) 15 c) c) 20 7/23 d) 25 e) None of these

Last Answer : % profit = Loss/Actual Weight x 100 = 500 – 425/500 × 100 = 75/500 x 100 = 15% Answer: b)

Description : A sum of Rs. 1550 was lent partly at 5% and partly at 8% per annum simple interest. The total interest received after 4 yr was Rs. 400. The ratio of the money lent at 8% to that lent at 5% is? (a) 15:16 (b) 16:17 (c) 19:17 (d) 21:26 (e) 20:17

Last Answer : (a) 15:16

Description : Sanki purchased 20 dozen notebook at Rs. 48 per dozen. He sold 8 dozen at 10% profit and remaining 12 dozen with 20% profit. What is his profit percentage in the transaction? A. 8% B. 15% C. 16% D. 19% 

Last Answer : Answer – C (16%) Explanation – C.P of 20 dozen = Rs.(48 x 20) = Rs.960 C.P of 8 dozen = Rs. (48 x8) = Rs. 384. C.P of 12 dozen =Rs. (960 – 384) = Rs. 576 Total S.P = Rs. (110/100 x 384 +120/100 x 576) = Rs.1113.60 ∴ Profit % = (153.60/960 x 100)% =16%

Description : The average age of a family of 6 members is 22 years. If the age of the youngest member be 7 years, then what was the average age of the family at the birth of the youngest member? A.15 B.18 C.28 D.24 E.None of these

Last Answer : Answer – B (18) Explanation – Total age of all members = 6 x 22 = 132 years 7 years ago, total sum of ages = 132 – (6 x 7) = 90 years But at that time there were 5 members in the family Average at that time = 90 /5 = 18 years

Description : The profit after selling a pair of trousers for Rs 863 is same as loss incurred after selling the same pair of trousers for Rs 631. What is the cost price of the trousers? 1. Rs7472. Rs 800 3. Rs 763 4. Cannot be determined

Last Answer : 1. Rs7472

Description : The average daily wages of 450 workers in a factory is Rs.45/- and the average daily wages of 340 workers in another factory is Rs.60/-.What is the approximate average daily wages of workers from both the factories together? a) Rs.61 b) Rs.59 c) Rs.70 d) Rs.51 e) Rs.60

Last Answer : Total wages of a factory =450 x 45= Rs. 20250/ Total wages of another factory = 340 x 60 = Rs. 20400 Total average = 20250 + 20400/450 + 340 = 40650/790 = 51.46 = Rs. 51 Answer: d)

Description : A two digit number exceeds forty percent of another two digit number by 16. If the sum of these two digit numbers is 72, which of the following is the difference between these two digit numbers ? a) 10 b) 6 c) 8 d) 14 e) None of these

Last Answer : c) 8 Let first two digit no. and second two digit no. be x and y respectively. x = y × 40/100 +16 x - 2y/5 = 16....(i) x + y = 72...(ii) From equation (i) and (ii) x = 32, y = 40 Difference = 8 Answer: c)

Description : Cost of fencing a circular plot at the rate of Rs.15 per metre is Rs.3, 300. What will be the cost of flooring the plot at the rate of Rs.100 per square metre? a) Rs.3, 85,000 b) Rs.4, 70,000 c) Rs.2, 25,000 d) Rs.3, 50,000 e) Rs.2, 95,000

Last Answer : Perimeter of plot = 3300/15 = 220 meter 2πr = 220 2 × 22/7 × r = 220 r = 35 m. Area of plot = πr^2 = 22/7 × 35 × 35 = 3850 mt^2 Cost of flooring = 3850 × 100=Rs. 385000 Answer: a)

Description : Speed of a boat in standing water is 9kmph and the speed of the stream is 1.5kmph. A man rows to a place at a distance of 10.5 km and comes back to the starting point. Find the total time taken by him. A.24 hours B.16 hours C.20 hours D.15 hours

Last Answer : Answer- A Basic Formula: i. speed = distance traveled / time taken ii. speed of the stream = ½ (a-b) km/hr iii. speed in still water = ½ (a+b) km/hr Explanation: Speed in still water= ½ (a+b) = 9km ... gives a = 10.5km/hr ; b=7.5 kmphr Total time taken by him = 105/10.5 + 105/7.5 = 24 hours

Description : A and B are 3 years and 2 years old respectively. Their father is 40 years. After how many years, father’s age would be twice of combined age of A and B? a) 5 years b) 10 years c) 15 years d) 20 years e) None of these

Last Answer : Father’s age = 40 years. Children’s combined age = 3 + 2= 5 years Double of their ages = 2 × 5 = 10 years Difference between father’s age and combined age = 40 – 10 = 30 years required time = 1/ (2 + 1) × 30 = 10 years Answer: b)