Choose the set of numbers, from the following, that is similar to the set (31, 19, 41).

1.(27, 29, 47)

2.(23, 34, 49)

3.(29, 16, 41)

4.(29, 17, 37)

5.(23, 37, 49)

A1, 3 & 5 only

B1 & 2 only

C2 & 4 only

D4 only ✓ Correct

Correct answer: (D) 4 only

Explanation

Only set 4 is similar, as (31, 19, 41) consists entirely of prime numbers.

The shared property to test is that all three members are prime.

Each candidate is checked for primality of all three entries.

The only set where 29, 17 and 37 are each prime is the fourth.

Sets built around 27, 34, 16 or 49 include composite numbers.

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