Math
posted by Anthony on .
I am thinking of a threedigit number. If you subtract 5 from it, the result is divisible by 5. If you subtract 6 from it, the result is divisible by 6 and if you subtract 7 from it, the result is divisible by 7. What is the smallest number that will satisy these conditions?

" If you subtract 5 from it, the result is divisible by 5" > number could be 5,10,15,20....
" If you subtract 6 from it, the result is divisible by 6 "
> number could be 6, 12, 18 , ...
" if you subtract 7 from it, the result is divisible by 7"
> number could be 7,14
so it must be a multiple of 5,6, and 7
5x6x7 = 210
check:
210  5 is divisible by 5
2106 is divisible by 6
2107 is divisible by 7
yup! It's 210