Question

Which of the following numbers is not divisible by 15?

• A. 135
• B. 235
• C. 435

Answer 1

The correct option is B 235

We know that for a number to be divisible by 15, it must be divisible by 3 and 5.

135, 235 and 435 is divisible by 5
($\because$ last digit of 135, 235 and 435 is 5)

135 and 435 is divisible by 3
($\because$ Sum of digits of $135\to (1+3+5=9$) and $435\to (4+3+5=12$) are multiple of 3)

235 is not divisible by 3
($\because$ Sum of digits of $235\to (2+3+5=10$) is not a multiple of 3)

As 135 and 435 is divisible by both 3 and 5, the numbers are also divisible by 15.