Question

Which number will replace the question mark (?) in the following number series?

1713, 1311, 117, 75, ?

1. 48
2. 59
3. 53
4. 39

Answer 1

Correct Answer - Option 3 : 53

The logic follows here is:

The given numbers are a pair of prime numbers and their preceding prime numbers.

1713 → 17 & 13 both are prime numbers.

1311 → 13 & 11 both are prime numbers.

117 → 11 & 7 both are prime numbers.

75 → 7 & 5 both are prime numbers.

And the series is decreasing in order.

So, the next number would be pair of 53.

53 → 5 & 3 both are the prime numbers.

Thus, the correct answer is "53".