SSC GD 2021 PYQ — Question 56

SSC GD Constable (English) - 7th December 2021 Shift 1 • Quantitative Aptitude • Q56

The greatest number that divides 415, 688 and 825 leaving 7, 8 and 9 as remainders, respectively, is:

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. 136.

Numbers which are completely divisible = (415 - 7) = 408

= 688 - 8 = 680 and

= 825 - 9 = 816

By prime factorization, we get

⇒ 408 = 23 × 3 × 17

⇒ 680 = 23 × 5 × 17

⇒ 815 = 24 × 3 × 17

Required HCF = 23 × 17 = 8 × 17

= 136