# Aptitude - Number System Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to Number System. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz. Q 1 - What is the result of the following?

` 4 + 44 + 444 + 4.44 `

A - 486.44

B - 444

C - 496.44

D - 44

### Explanation

496.44

Q 2 - The sum of even numbers between 1 and 21 is?

A - 110

B - 100

C - 70

D - 30

### Explanation

A.P -> a = 2, l = 20
-> a + (n - 1)d = 20
-> 2 + (n - 1) x 2 = 20
-> n = 10 i.e. terms = 10
S2 = n2 (a + l)
= 102 x (2 + 20)
= 110

Q 3 - Which of the following is a prime number?

A - 24

B - 35

C - 125

D - 151

### Explanation

151 is greater than 12
All prime numbers less than 12 is 2, 3, 5, 7, 11
24 is divisible by 3 i.e. not prime
35 is divisible by 5 i.e. not prime
125 is divisible by 5 i.e. not prime
151 is divisible by 2, 3, 5, 7, 11 i.e. prime number.

Q 4 - How many natural numbers are there between 17 and 9 which are exactly divisible by 6?

A - 13

B - 15

C - 14

D - 16

### Explanation

Numbers -> 18, 24, 30, ... , 90
A.P: a = 18, d = 6, l = 90
tn = a + (n-1)d
90 = 18 + (n-1)6
90 = 18 + 6n -6
n = 13

Q 5 - A number when divided by 296 leaves 75 as remainder. When the same number is divided by 37, the remainder will be?

A - 3

B - 0

C - 1

D - 5

### Explanation

Lets x = 296q + 75 = (37 + 8q + 37 x 2) + 1
= 37 + (8q + 2) + 1
When the number is divided by 37, the remainder is 1.

Q 6 - What is the unit digit in 2137754 ?

A - 1

B - 3

C - 7

D - 9

### Explanation

`  unit digit in (2137)754 = unit digit in (7)754 = unit digit in (74)188 x 72 = unit digit in (1 x 49) = 9 Thus Unit digit in (2137)754 is 9.  `

Q 7 - 916 x y x 3 = 214344. What is y?

A - 78

B - 68

C - 84

D - 66

### Explanation

` 916 x y x 3 = 214344 => 2748 x y = 214344 => y = 214344 / 2748 => y = 78  `

Q 8 - (y)2 = 351649. What is y?

A - 433

B - 583

C - 623

D - 5

### Explanation

`  y = 1008 x 992     = (1000 + 8) x (1000 - 8)  Using formulae (a+b)(a-b) = a2 - b2  ∴ y =  (1000)2 - (8)2  = 1000000 - 64  = 999936  `

Q 9 - What is the first prime number?

A - 0

B - 1

C - 2

D - 3

### Explanation

2 is the first prime number.

Q 10 - 517p324 is divisible by 3. What is minimum p?

A - 0

B - 1

C - 2

D - 3

`    5 + 1 + 7 + p + 3 + 2 + 4  = 22 + x  which is divisible by 3  ∴ x = 2  `