14
Q:

# The average age of 7 boys is increased by 1 year when one of tem whose age is replaced by a girl. What is the age of the girl ?

 A) 33 yrs B) 27 yrs C) 21 yrs D) 29 yrs

Explanation:

Let the avg age of 7 boys be 'p' years
Let the age of the girl be 'q' years
From given data,
The age of 7 boys = 7p years
Now the new average = (p + 1) when 22 yrs is replaced by q
Now the age of all 7 will become = 7(p + 1) yrs
Hence, 7p - 22 + q = 7(p + 1) yrs
7p - 22 + q = 7p + 7
q = 22 + 7 = 29

Therefore, the age of girl = q = 29 years.

Q:

Ian has 14 boxes of paper and divides them evenly between 4 coworkers. How many whole boxes did each coworker get?

 A) 2 B) 2.5 C) 3 D) 3.5

Explanation:

Given number of boxes = 14

Number of workers = 4

Now, number of whole boxes per worker = 14/4 = 3.5

Hence, number of whole boxes per each coworker = 3

1 552
Q:

Five boxes of bananas sell for Rs. 30. how many boxes can you buy for Rs.9?

 A) 2 B) 1.5 C) 1.25 D) 2.5

Explanation:

Given Five boxes of bananas sell for Rs. 30.

=> 1 Box of Bananas for = 30/5 = Rs. 6

Then, for Rs. 9

=> 9/6 = 3/2 = 1.5

Hence, for Rs. 9, 1.5 box of bananas can buy.

6 448
Q:

Third proportion of 10 and 20 is

 A) 30 B) 40 C) 25 D) 20

Explanation:

The third proportional of two numbers p and q is defined to be that number r such that

p : q = q : r.

Here, required third proportional of 10 & 20, and let it be 'a'

=> 10 : 20 = 20 : a

10a = 20 x 20

=> a = 40

Hence, third proportional of 10 & 20 is 40.

4 620
Q:

The average weight of 45 passengers in a bus is 52 kg. 5 of them whose average weight is 48 kg leave the bus and other 5 passengers whose average weight is 54 kg join the bus at the same stop. What is the new average weight of the bus?

 A) 54.21 kgs B) 51.07 kgs C) 52.66 kgs D) 53.45 kgs

Explanation:

Given total number of passengers in the bus = 45

First average weight of 45 passengers = 52 kgs

Average weight of 5 passengers who leave bus = 48

Average weight of passengers who joined the bus = 54

Therefore, the net average weight of the bus is given by

21 1436
Q:

12 boys decided to constribute Rs. 750 each to an Orphange. Suddenly few of them boys dropped out and consequently the rest had to pay Rs. 150 more. Then the number of boys who dropped out?

 A) 4 B) 6 C) 2 D) 3

Explanation:

Total money decided to contribute = 750 x 12 = 9000

Let 'b' boys dropped

The rest paid 150/- more

=> (12 - b) x 900 = 9000

=> b = 2

Hence, the number of boys who dropped out is 2.

17 1612
Q:

P, Q, R, S, T and U are six consecutive odd numbers and their average is 52. What is the product of P and U ?

 A) 2212 B) 2154 C) 2349 D) 2679

Explanation:

Let x, x+2, x+4, x+6, x+8 and x+10 are six consecutive odd numbers.

Given that their average is 52

Then, x + x+2 + x+4 + x+6 + x+8 + x+10 = 52×6

6x + 30 = 312

x = 47

So Product = 47 × 57 = 2679

14 1716
Q:

19 friends went to a restaurant for a combined weekend dinner party. 13 of them spent Rs. 79 each on their dinner and the rest spent Rs. 4 more than the average expenditure of all the 19. What was the total money spent by them?

 A) Rs. 1398.96 B) Rs. 1457.09 C) Rs. 1662.35 D) Rs. 1536.07

Explanation:

Let average expenditure was Rs. R

13 x 79 + 6x(R + 4) = 19R

=> R = Rs. 80.84

Total money = 19 x 80.84 = Rs. 1536.07.

21 1580
Q:

The average age of a class is 19 years. While the average age of girls is 18 and that of boys is 21. If the number of girls in the class is 16, Find the number of Boys in the class?

 A) 12 B) 10 C) 8 D) 6

Explanation:

Let the number of boys = x

From the given data,

=> [21x + 16(18)]/(x+16) = 19

=> 21x - 19x = 19(16) - 16(18)

=> 2x = 16

=> x = 8

Therefore, the number of boys in the class = 8.