1

Arithmetic Aptitude 2

Question 1
512 x 512 + 488 x 488 = ?
A
512438
B
502568
C
500288
D
514318
Arithmetic Aptitude 2    Simplification and Approximation    
Discuss it


Question 1 Explanation: 
X2 + Y2 = 1/2[(X + Y)2 + (X – Y)2]
5122 + 4882 = ½ [(512+488)2 + (512-488)2]
= 1/2[10002+242]
= 1/2(1000000+576)
= 500288
Question 2
The sum of all 3 digit numbers divisible by 3 is:
A
165150
B
164380
C
168420
D
165250
Arithmetic Aptitude 2    Number Divisibility    
Discuss it


Question 2 Explanation: 
All 3 digit numbers divisible by 3 are :
102, 105, 108, 111, ..., 999.

This is an A.P. with first element 'a' as 
102 and difference  'd' as 3.

Let it contains n terms. Then,
102 + (n - 1) x 3 = 999 
102 + 3n-3 = 999
3n = 900 or n = 300
Sum of AP = n/2 [2*a  + (n-1)*d]
Required sum = 300/2[2*102 + 299*3] = 165150. 
Question 3
Which of Following is not divisible from 4 ?
A
546702
B
556824
C
367312
D
467536
Arithmetic Aptitude 2    Number Divisibility    
Discuss it


Question 3 Explanation: 
If last 2 digits are divisible by 4, then number is also divisible by 4.
In case of 546702 last 2 digits are 02 (x)
In case of 556824 last 2 digits are 24 (/)
In case of 367312 last 2 digits are 12 (/)
In case of 467536 last 2 digits are 36 (/) 
Question 4
What should be the value of * in 985*865, if number is divisible by 9?
A
6
B
5
C
4
D
0
Arithmetic Aptitude 2    Number Divisibility    
Discuss it


Question 4 Explanation: 
If a number is divisible by 9, the sum of digits is also divisible by 9
9 + 8 + 5 + * + 8 + 6 + 5 = 9x
41 + * = 9x
Nearest value of 9x must be 45
41 + * = 45
* = 4
Question 5
The least perfect square, which is divisible by each of 15, 20 and 36 is:
A
1200
B
800
C
1000
D
900
Arithmetic Aptitude 2    Number Divisibility    
Discuss it


Question 5 Explanation: 
LCM of 15, 20 and 36 is 180

Now 180 = 3 x 3 x 2 x 2 x 5

To make it perfect square, it must
be multiplied from 5.

So required no. = 32 x 22 x 52 = 900
Question 6
What should be the value of x in equation (x / √216) = (√96 / x)
A
12
B
13
C
9
D
11
Arithmetic Aptitude 2    Simplification and Approximation    
Discuss it


Question 6 Explanation: 
Let (x / √216) = (√96 / x)

Then x2 = √(216 x 96)
       = √(36 x 2 x 3 x 16 x 2 x 3)
       = √(62 x 42 x 22 x 32)
       = 6 x 4 x 2 x 3
       = 144
Or x = 12
Question 7
Sum of 4 childeren born at interval of 4 years is is 36. What is the age of youngest child?
A
2 years
B
3 years
C
4 years
D
5 years
Arithmetic Aptitude 2    Age    
Discuss it


Question 7 Explanation: 
Let the ages of children be x, (x+4), 
(x+8) and (x+12) years.

Then x + x + 4 + x + 8 + x +12 = 36
                       4x + 24 = 36
                             4x = 12
                              x = 3
Age of the youngest child = x = 3 years
Question 8
A is 5 years older than B who is thrice as old as C. If the total of ages of A, B and C is 40, then how old is C ?
A
6
B
7
C
5
D
8
Arithmetic Aptitude 2    Age    
Discuss it


Question 8 Explanation: 
Let C’s age be x years then B’s age be 3x
years and A’s age be (3x+5) years

Therefore  x + 3x + (3x + 5) = 40
                      7x + 5 = 40
                          7x = 35
                            x = 5
There are 8 questions to complete.
1

Company Wise Coding Practice    Topic Wise Coding Practice