SSC CHSL 20 Dec 2015 Shift 2 Paper

Question : 141 of 200

Marks: +1, -0

The number

142^2-1

is divisible by

Solution:

Number =

(142) ^2 − (1) ^2

Using,

a^2 − b ^2 = (a − b)(a + b)

(142 − 1)(142 + 1)

141 × 143

(3 × 47) × (11 × 13)

Thus, it is divisible by 13.

Go to Question:

Prev Question

Next Question