Which of the following number is divisible by 24 ?
A. 61212
B. 512216
C. 31214
D. 3125832
Answer: D
Solution:
24 = 3 × 8 where 3 and 8 are co-prime numbers. 3 and 8 are also factors of 24.
Hence, (1) If a number is divisible by 3 and 8, the number will be divisible by their product 24 also. (2) If a number is not divisible by 3 or 8, it is not divisible by 24
61212 is not divisible by 8 though it is divisible by 3 => 61212 is not divisible 24
512216 is not divisible by 3 though it is divisible by 8 => 512216 is not divisible 24
31214 is not divisible by 3 and 8 => 31214 is not divisible 24
3125832 is divisible by 3 and 8 => 3125832 is divisible 24
