number system Model Questions & Answers, Practice Test for ibps rrb clerk asst multipurpose prelims 2024

Answer: (b)

Statement I:

Divisibility rule of 11: The difference between the sum of even places and the sum of odd places is 0 or that number is divisible by 11.

Difference = Sum of odd place – Sum of even place = 13 – 13 = 0, it is divisible by 11.

Statement II:

173 is square of approximately 13.

So, below 13 prime number are - 2, 3, 5, 7, 11

Now, 173 is not divisible by 2, 3, 5, 7 and 11.

So, it is a prime number.

So, both the statements I and II are correct.

Answer: (c)

Prime number:

A number that is divisible by itself and one excluding one.

So, 1 is not prime number.

Composite Number:

Natural numbers, which has more than 2 distinct factors are called composite numbers.

1 is not composite numbers.

Answer: (b)

38808 = $2^3 × 3^2 × 7^2 × 11$

∴ Number of divisors = (3 + 1)(2 + 1)(2 + 1)(1 + 1)

= 4 × 3 × 3 × 2 = 72

On excluding number '1' and '38808'.

Number of divisors = 72 – 2 = 70

Answer: (b)

The answer will be 50 since, 125*122 will give 50 as the last two digits.

Answer: (c)

Divisor = [Sum of remainders]

– [ Remainder when sum is divided]

= 11 + 21 – 4 = 28