Practice MCQ Questions and Answer on Number System

21.

Among the following statements, the statement which is not correct is :

  • (A) Every natural number is an integer.
  • (B) Every natural number is a real number.
  • (C) Every real number is a rational number.
  • (D) Every integer is a rational number.

22.

A number of boys raised Rs. 400 for a famine relief fund, each boy giving as many 25 paise coins as there were boys. The number of boys was -

  • (A) 40
  • (B) 16
  • (C) 20
  • (D) 100

23.

The unit's digit in the product 274 × 318 × 577 × 313 is :

  • (A) 2
  • (B) 3
  • (C) 4
  • (D) 5

24.

$$\frac{1}{5}$$ of a number exceeds $$\frac{1}{7}$$ of the same number by 10. The number is -

  • (A) 25
  • (B) 150
  • (C) 175
  • (D) 200

25.

The sum of four consecutive two-digit odd numbers, when divided by 10, become a perfect square. Which of the following can possibly be one of these four numbers?

  • (A) 21
  • (B) 25
  • (C) 41
  • (D) 67

26.

Which of the following number is not divided by 18 ?

  • (A) 54036
  • (B) 50436
  • (C) 34056
  • (D) 65043

27.

The largest among the numbers ?

  • (A) $${\left( {0.1} \right)^2}$$
  • (B) $$\sqrt {0.0121\,} $$
  • (C) 0.12
  • (D) $$\sqrt {0.0004} $$

28.

Which one of the following numbers is divisible by 3 ?

  • (A) 4006020
  • (B) 2345678
  • (C) 2876423
  • (D) 9566003

29.

Between two distinct rational numbers a and b, there exists another rational number which is :

  • (A) $$\frac{a}{2}$$
  • (B) $$\frac{b}{2}$$
  • (C) $$\frac{ab}{2}$$
  • (D) $$\frac{a + b}{2}$$

30.

What decimal of a week is an hour ?

  • (A) 0.0059
  • (B) 0.0062
  • (C) 0.062
  • (D) 0.059