Question

If a four-digit number 52Z8 is divisible by 3 and 9,then Z is:

Answer 1

Divisibility rule of 3:--
if Z=2
=5+2+2+8
=8
8 is not divisible by 3
so z is not 2

if Z=3
=5+2+3+8
=9

9 is divisible by 3

HENCE, Z=9

HOPE IT HELPS

Answer 2

Hey there!!

According to rule of divisibility, if a number is divisible by 3 or 9, the sum of digits is also divisible by 3 or 9 respectively.

So if 52Z8 is divisible by 3 or 9.

The sum of its digits is also divisible by 9(I'm not taking 3 because every number which is divisible by 9, exactly divisible by 3).

Hence sum = 5+2+Z+8

= 15 + Z

If 15 + Z is divisible by 9, then number must be 18.

=) 15 + Z = 18

=) Z = 18-15

=) Z = 3

Hope it helps uh!!