Subject: General Aptitude · Chapter: Number System · Exam: · Marks: · Difficulty:
Which of the following numbers is exactly divisible by 24?
(a)35718
(b)63810
(c)537804
(d)3125736
Answer
Answer (as printed): D
Explanation
We have 24 = 3 × 8, where 3 and 8 are co-primes. Clearly, 718 is not divisible by 8. So, 35718 is not divisible by 8. 810 is not divisible by 8. So, 63810 is not divisible by 8. 804 is not divisible by 8. So, 537804 is not divisible by 8. 736 is divisible by 8. So, 3125736 is divisible by 8. Also, sum of its digits = (3 + 1 + 2 + 5 + 7 + 3 + 6) = 27, which is divisible by 3. So, 3125736 is divisible by 3 also. Hence, it is divisible by 24.
Explanation as extracted from the printed page; notation may be imperfect.