Question

On dividing a positive integer n by 9, we get 7 as remainder. What will be the remainder if (3n – 1) is divided by 9?

Options

• 1

• 2

• 3

• 4

Answer 1

2

Explanation:

Write n = 9k + 7.

Then 3n – 1 = 3(9k + 7) – 1

= 27k + 20

= 9(3k) + 2

So, the remainder on division by 9 is 2.