Changing values in one cell depending on drop down

Hello,
I created a drop-down list of scores (ie. 10, 20, 30 to 100) in cell A1. In cell B1 I want it to show a specific number value based on which selection has been chosen in the drop-down. So if I select 10 or 20 in Cell A1, it shows 1 in Cell B1 and similarly, if I select 90 or 100 in Cell A1 it shows 5 in Cell B1.

I have tried using the IF function =IF(A1="10",1,IF(A1="20",1,IF(A1="30",2,"")))

But it does not seem to work.

Does anyone know how to fix this formula to achieve this?