Numbers Aptitude Questions with Answers

1.In a 2 digit numbers, the digit in the unit’s place is 2 times the digit in 10’s place and sum of the digits is equal to 9. What is the number?

30 16 36 56

2.The difference between a 2 digit numbers & the number getting by place changing the 2 digits is 54. What is the difference between the 2 digits of that particular number?

5 6 7 8

3.The sum of the digits of a 2 number is 2/5 of the difference between the number and the number obtained by place changing the positions of the particular digits. What is the exact difference between the particular digits of the number?

5 6 Cannot be determined None of these

4.The difference between 2 numbers is 1356. When the largest number is divided by the smallest one, the quotient is 6 and the remainder is 15. The smaller number is ?

570 270 370 470

5.If the number getting on position changing the digits of a 2 digit number is 18 more than the original number and the sum of the digits is 6. What is the particular original number?

42 52 62 72

6.The product of 4 consecutive even numbers is always divisible by?

384 284 584 684

7.The sum of two positive integers multiplied by the bigger number is 204, and their difference multiplied by the smaller number is 35. What are the numbers?

12,5 13,5 14,5 16,5

8.The product of two numbers is 9375 and the quotient, when the larger one is divided by the smaller, is 15. What is the sum of the numbers?

500 400 600 700

PROBLEMS ON NUMBERS -> DESCRIPTION

In this section, questions involving a set of numbers are put in the form of a puzzle. You have to analyse the given conditions, assume the unknown the numbers and form equations accordingly, which on solving yield the unknown numbers.

AVERAGE -> IMPORTANT FACTS AND FORMULAE 

I. Average = [Sum of observations / Number of observations] 

II. Suppose a man covers a certain distance at x kmph and an equal distance at y kmph. Then, the average speed during the whole journey is [2xy / x + y] kmph.

Numbers -> IMPORTANT FACTS AND FORMULAE 

1. Natural Numbers : Counting numbers 1, 2, 3, 4, 5, .. are called natural numbers. 

II. Whole Numbers : All counting numbers together with zero form the set of whole numbers. 

Thus, I. 0 is the only whole number which is not a natural number.  

II. Every natural number is a whole number. 

III.Some Important Formulae :

 I. ( 1 + 2 + 3 + .....+ n) = n (n + 1 ) / 2 

II. (1 2 + 22 + 32 + ..... + n2) = n ( n + 1 ) (2n + 1) / 6 

III. (1 3 + 23 + 33 + ..... + n3) = n2 (n + 1)2 / 4 

Numbers

1. (935421 x 625) = ?
A. 542622125	B. 584632125
C. 544638125	D. 584638125

2. Which of the following is a prime number ?
A. 9	B. 8
C. 4	D. 2

3. What is the largest 4 digit number exactly divisible by 88?
A. 9944	B. 9999
C. 9988	D. 9900

Answer : Option A

Explanation :

Largest 4 digit number = 9999

9999 ÷ 88 = 113, remainder = 55

Hence largest 4 digit number exactly divisible by 88 = 9999 - 55 = 9944

4. {(481 + 426)2 - 4 x 481 x 426} = ?
A. 3025	B. 4200
C. 3060	D. 3210

Here, the given statement is like (a + b)² - 4ab where a= 481 and b = 426

(a + b)² - 4ab = (a² + 2ab + b²) - 4ab = a² - 2ab + b² = (a - b)²