Question

What is 90% of 120?

Answer 1

I found: `108`

Explanation:

Our trick here is to think that a fraction in `%` land is the same as the correspondent in "number" land; so we can write:
`(100%)/(90%)=120/x`
Where `x` is the correspondent of `90%` in numbers.
Rearranging:
`x=120*(90cancel(%))/(100cancel(%))=108`