9 different possible tiles to choose, but there are duplicates of two types of tiles. Out of 9 tiles, two of them are S. Therefore, the probability you choose an S is 2/9 (however much percent that is).
You'd reverse the math for letters other than P:
Out of 9 tiles, two of them are P. 9 minus 2 is seven. Seven out of 9 characters are not the letter P. Therefore, the probability you choose any letter other than P is 7/9 (however much percent <em>that </em>is).
If Sarah has three times as many pencils as Mike she has 3 times the number of pencils Mike has which is equivalent to 3 * m. That means Mike has m pencils and Sarah has 3m pencils. they have m + 3m pencils. The expression would be total: m + 3m.
