Countif and divide by formula needs to become percentage

OK, stuck again gang!

I have a spreadsheet where C3 has a capital X as the text in it. Cells E3 through E22 have a value in each of them ranging from 1 to 5. I want to calculate that if C3 has an X, and E3 through E22 has a 5, 4 or 3, then add the number of cells with those values and divide by the total number of cells that E3 through E22 have an X and get a percentage.

Here's my formula so far; =IF(C3:C22="X",COUNTIF(E3:E22, "5")+COUNTIF(E3:E22, "4")+COUNTIF(E3:E22, "3"))/(C3:C22="X")*100

I think it's the back end of the formula that is having issues.