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Which of the following CANNOT be a factor of the number N = 527,P90? P is the hundred's digit of N.

A. 9
B. 3
C. 4
D. 7
E. 10

Without knowing P how is it possible to find out the factors of a number?

Am I missing something

This problem requires us to know the concept of "test of divisibility".

A number is divisible by 4 only if the last two digits are divisible by 4. since '90' is not divisible by 4, N = 527,P90 is NEVER divisible by 4, irrespective of the value of P.

N is definitely divisible by 10. Depending on the value of P, N could be divisible by 9, 3, and 4.

Answer: C

Thanks. Can you please post different tests of divisibility. I know sum of digits should be divisible by 3 for 3.