CUET PG 2021 — Reasoning PYQ

Example Group: $13,17,23,27,31$

1. Analyze the properties of each number:

• $13$: Only divisible by $1$ and itself.

• $17$: Only divisible by $1$ and itself.

• $23$: Only divisible by $1$ and itself.

• $27$: Divisible by $1,3,9,27$.

• $31$: Only divisible by $1$ and itself.

2. Identify the pattern:

In this group, four numbers are Prime Numbers, while one is a Composite Number.

• $13,17,23,31\in \text{Prime Numbers}$

• $27\in \text{Composite Numbers}$

3. Mathematical Logic:

The set of prime numbers $P$ is defined as:

Since $27$ has divisors other than $1$ and itself:

Conclusion:

In this specific group, $27$ is the "different" (odd one out) number.