If ` 2a 25 ` is a multiple of 9, where a is digit, what is the values of `a` ?

Explanation

Given,`2a25` is a multiple of `9`.
Divisibility rule of `9`: Sum of all digits.
`2+a+2+5=9+a`
`9+a` is a multiple of `9`.
Here, we can choose any multiple of `9: 9,18,27....81`
`9+a=9`
`=>a=9-9`
`=>a=0`
Or
`9+a=18`
`=>a=18-9`
`=>a=9`
Hence,the possible numbers are `0` and `9`.