Model Aptitude questions and answers for placement - Set 5

1)   What will come in place of (a) in the following expression?

a - 796.21 + 498.05 = 215.50 – 425.01


a. 71.81
b. 81.71
c. 84.74
d. 88.65
e. None of these
Answer  Explanation 

ANSWER: 88.65

Explanation:
a - 796.21 + 498.05 = 215.50 - 425.01
a = 88.65


2)   A boy pays Rs. 369 for an article marked at Rs. 600, by enjoying two successive discounts. If the first discount is of 25%, how much should be the second discount?

a. 20 %
b. 10 %
c. 25 %
d. 18 %
e. None of these
Answer  Explanation 

ANSWER: 18 %

Explanation:
First discount = 25% of 600 = Rs. 150.
Thus, the reduced price = 600 – 150 = Rs. 450.
Since the person actually paid Rs. 369, the value of the second discount must be equal to Rs. 81 (450 – 369).
Let the second discount be x
Thus, we get, 81 = x of 450
( 81/450)*100 = 18%


3)   A housewife wishes to purchase three articles A, B and C from a sum of Rs. 200. The unit prices of the articles A, B and C are Rs. 20, Rs. 35 and Rs. 25 respectively. If she spends the entire amount by purchasing 5 numbers of articles of type C, what is the ratio of the number of articles purchased of type A to that of, type B?

a. 1 : 2
b. 2 : 1
c. 1 : 1
d. None of these
e. Cannot be determined
Answer  Explanation 

ANSWER: 2 : 1

Explanation:
After spending Rs. 125 (25 * 5) for articles of type C, the housewife is left with Rs. 75 (200 – 125). Since this amount has to be spent in totality, she must have purchased 2 articles of type A (equivalent to Rs. 40) and 1 article of type B (equivalent to Rs. 35). Thus, the required ratio is 2 : 1.


4)   A person can go from place “P” to “Q” by 7 different modes of transport, but is allowed to return back to “P” by any mode other than the one used earlier. In how many different ways can he complete the entire journey?

a. 42
b. 30
c. 11
d. 56
e. 65
Answer  Explanation 

ANSWER: 42

Explanation:
The person can travel from “P” to “Q” in any of the 7 different modes of transport. However, while returning, he cannot use the mode which he used earlier. Thus, while returning, he has the option of only 6 different modes of transport. Hence, the total number of ways would be 7 * 6 = 42.


5)   A briefcase has a number-lock system containing a combination of 3 digits (Each digit can be of numbers 0 to 8). If the correct combination is unknown, how much maximum time would be required to open the bag if each “trial” of combination takes 3 seconds?

a. 45.23 minutes
b. 36.45 minutes
c. 60.34 minutes
d. 90.15 minutes
e. 50.9 minutes
Answer  Explanation 

ANSWER: 36.45 minutes

Explanation:
Maximum number of trials required = 9 * 9 * 9 = 729. Since for each combination trial, 3 seconds are required to open the briefcase is given as 3 * 729 = 2187 seconds = 36.45 minutes.


6)   Out of the three numbers A, B and C, A exceeds B by 20 and C exceeds A by 55. If the sum of all the numbers is 230, What is the difference between the largest and the smallest number?

a. 52
b. 58
c. 63
d. 75
Answer  Explanation 

ANSWER: 75

Explanation:
We have , A = B + 20 & C = A + 55 = B + 75
Thus, (B + 20) + (B) + (B + 75) = 230
B = 45
Thus, A = 65 & C = 120. Hence, (C) – (B) = 120 – 45 = 75
Short-Cut Method : Since C is larger than A by 55 and A is larger than B by 20, we get, the Required difference = 55 + 20 = 75 (without calculating the actual values of A, B and C).


7)   If P * Q implies (P2 + Q2), 8 * (3 * 2) = ?

a. 646
b. 86
c. 233
d. 104
e. 640
Answer  Explanation 

ANSWER: 233

Explanation:
We have, P * Q = (P2 + Q2) ......... Given
8 * (3 * 2) = ?
8 * 13 = (64 +169) = 233


8)   If 148 is multiplied first by 163 and then by 236, Which of the following numbers would come at the unit's place?

a. 8
b. 6
c. 4
d. 3
e. None of these
Answer  Explanation 

ANSWER: 4

Explanation:
148 * 163 * 236 = 8 * 3 * 6 = 4 at the unit's place.
When the numbers are multiplied, the unit digit of the final product is obtained as the product of the unit digits of individual numbers.


9)   A trader purchases several articles at the rate of 13 for Rs. 10 and sells them at the rate of 10 for Rs. 13. What is his gain/loss?

a. 69 % gain
b. 56.25 % gain
c. 56.25 % loss
d. 25 % loss
e. None of these
Answer  Explanation 

ANSWER: 69 % gain

Explanation:
We have, C. P of 13 articles = Rs. 10
& S. P of 10 articles = Rs. 13
S. P of 13 articles = ?
= (13 * 13) / 10 = 16.9
Gain = [(16.9 – 10)/10] * 100 = 69 %


10)   On a shelf, 2 books of Geology, 2 books of Sociology and 5 of Economics are to be arranged in such a way that the books of any subject are to be together. Find in how many ways can this be done?

a. 3846
b. 2880
c. 900
d. 90
e. None of these
Answer  Explanation 

ANSWER: 2880

Explanation:
There are books of 3 subjects (Geology, Sociology and Economics), hence they can be arranged in 3! (3 * 2 * 1) = 6 ways.
Further, in each category (subject), books are to be arranged in different order, we get,
Required number of ways: 3! * [2! * 2! * 5!] = 2880