Where did i go wrong?

=IF(F4=' 100',"1",)OR(F4='76 - 100',"2",)OR(F4='51 - 75',"3",)OR(F4='26 -
50',"4",)OR(F4='< 25',"5")

Basically€¦

If F4 is equal €˜ 100 then display a 1 or, if F4 is equal to 76 €“ 100
then display a 2 or, if F4 is equal to 51 €“ 75 then display a 3