CSATNumber System & SeriesDivisibility Divisors and Remainder2016

If R and S are different integers both divisible by 5, then which of the following is not necessarily true?

A

R - S is divisible by 5

B

R + S is divisible by 10

C

R × S is divisible by 25

D

R² + S² is divisible by 5

Correct Answer: Option B

Explanation

This question asks which statement is 'not necessarily true'. I've seen this type of logical framing in previous papers, like in 2014 and 2015 [14,

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