CSATNumber System & SeriesBasic Arithmetic and Odd Even2023

Three of the five positive integers p, q, r, s, t are even and two of them are odd (not necessarily in order). Consider the following: 1. p + q + r - s - t is definitely even. 2. 2p + q + 2r - 2s + t is definitely odd. Which of the above statements is/are correct?

A

1 only

B

2 only

C

Both 1 and 2

D

Neither 1 nor 2

Correct Answer: Option A

Explanation

We have a set of 5 numbers: 3 are Even, 2 are Odd. Let's analyze the statements using basic parity rules [1], [66]. **Statement 1:** `p + q + r - s - t` is definitely even. In parity logic, subtraction is the same as addition. So

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