Model Aptitude questions and answers for placement - Set 4

1)   A, B and C enter into partnership. A invests 3 times as much as B invests and B invests two third of what C invests. At the end of the year, the profit earned is Rs. 8500. What is the share of B?

a. Rs. 1245.50
b. Rs. 1623.53
c. Rs. 1545.45
d. Rs. 1145.15
Answer  Explanation 

ANSWER: Rs. 1545.45

Explanation:
Let C's capital = Rs. y. Then, B's capital = Rs. (2/3)y
A's capital = Rs. (3 × (2/3)y) = Rs. 2y
Therefore, ratio of their capitals
= 2y : (2/3)y : y
= 6 : 2 : 3
Hence, B's share = Rs. (8500 x 2/11) = Rs. 1545.45


2)   If 36 men can do a piece of work in 25 hours, in how many hours will 10 men do it?

a. 100 hours
b. 90 hours
c. 60 hours
d. 30 hours
Answer  Explanation 

ANSWER: 90 hours

Explanation:
Let the required numbers of hours be X.
Less men, More hours (Indirect proportion)
Therefore, 10 : 36 :: 25 : X = (10 x X) = (36 x 25) = X = (36 x 25)/10 = 90.
Hence, 10 men can do it in 90 hours.


3)   What is the value of (12 + 22 + 32 + 42 + ----- + 102)

a. 295
b. 324
c. 385
d. 391
Answer  Explanation 

ANSWER: 385

Explanation:
(12 + 22 + ….. + n2) = (1/6) n(n + 1) (2n + 1)
Here, n = 10
Therefore,
(12 + 22 + ….. + 102) = (1/6) 10 (10 + 1) ( 2 x 10 + 1)
= (1/6) x 10 x 11 x 21
= 385


4)   By purchasing an article at 20 % discount on the original price and then selling it at a price of 25% above the original price, a trader earns Rs. 200 as the profit. What was the original price of the article?

a. Rs. 444.44
b. Rs. 255.50
c. Rs. 100.10
d. Rs. 810
e. None of these
Answer  Explanation 

ANSWER: Rs. 444.44

Explanation:
Let the original price of the article be Rs. 100. Hence the purchase price for the trader would be Rs. 80 and his selling price would be Rs. 125. Thus, he would earn a profit of Rs. 45 (125 – 80). Therefore,
Profit is Rs. 45 if the original price is Rs. 100
Hence, if profit is Rs. 200, then original price will be..
= 100x 200/45
= Rs. 444.44


5)   Shruti purchased several number of three articles P, Q and R in the proportion 3 : 2 : 3. If the unit costs of the articles P, Q and R are 200, Rs. 90 and Rs. 60 respectively, how many articles of Q must have been purchased in the total purchases of Rs. 4800?

a. 8
b. 10
c. 12
d. 14
e. None of these
Answer  Explanation 

ANSWER: 10

Explanation:
Let the number of articles of types P, Q and R be 3a, 2a and 3a respectively.
Thus, we get,
(200 x 3a) + (90 x 2a) + (60 x 3a) = 4800
960a = 4800
a = 5
Hence, the number of articles of type “Q” = 2x5 = 10


6)   A train travels a certain distance by taking 3 stops of 20 minutes each. Considering the period of stoppage, the overall speed of the train comes to 40 kmph; while without consideration of stoppage, it is 60 kmph. How much distance must the train have travelled ?

a. 170 kms
b. 120 kms
c. 270 kms
d. None of these
e. Cannot be determined
Answer  Explanation 

ANSWER: 120 kms

Explanation:
Let the time taken to travel the distance without taking stops be “b” hours.
Thus, we get,
60 x b = 40(b + 1)
b = 2
Thus, we get 60 x 2 = 120 kms


7)   Rohan was 4 times as old as his son 6 years ago. After 6 years Rohan will be twice as old as his son. What is son's present age?

a. 10 years
b. 12 years
c. 14 years
d. 18 years
Answer  Explanation 

ANSWER: 12 years

Explanation:
Let son's age 6 years ago be X years. Then, Rohan's age 6 years ago = 4X years.
Son's age after 6 years = (X + 6) + 6 = (X + 12) years
Rohan's age after 6 years = (4X + 6) + 6 = (4X + 12) years
Therefore 2(X + 12) = 4X + 12
2X = 12
X = 6
Hence, son's present age = (X + 6) = 12 years
Rohan's present age = (4X + 6) = 30 years


8)   If √10 = 3.16, find the value of If √5/2

a. 1.30
b. 1.58
c. 2.03
d. 2.15
Answer  Explanation 

ANSWER: 1.58

Explanation:
(5/2) =√(5×2/2×2)= √(10)/2 =3.16/2 = 1.58


9)   Find the average of first 30 natural numbers.

a. 12
b. 15.5
c. 14.5
d. 16
Answer  Explanation 

ANSWER: 15.5

Explanation:
Sum of first n natural numbers = n(n+1)/2
Hence, sum of first 30 natural numbers = (30 x 31)/2 = 465
Therefore, required average of = 465/30 = 15.5


10)   If logxy = 100 and log3x = 10, then the value of y is:

a. 310
b. 3100
c. 31000
d. 310000
Answer  Explanation 

ANSWER: 31000

Explanation:
log3x = 10
Hence,x= 310
logx y = 100
y =x100 = (310)100= y = 31000