Answer:
333
Step-by-step explanation:
It is a well known trick that if you add together the digits of a number and they are a multiple of 9, then the number will be divisible by 9. You can therefore start going through the 3 digit numbers as described and testing them.
111=1+1+1=3 or not a multiple of 9
222=2+2+2=6 or not a multiple of 9
333=3+3+3=9 A multiple of 9! This is the correct answer.
Hope this helps!
