How do you spell numbers like 91, 93, or 95? For example, is it "Ninty three" or "ninety three"?

When spelling numbers that include 90, you should always use the correct spelling "ninety."

For 91: ninety-one
For 93: ninety-three
For 95: ninety-five. The hyphen is standard when writing out compound numbers from 21 to 99.