Excel And,IF and Datedif

Excel intermediate course

I would to use a multiple IF statement between two dates (years as 1 whole number).

This is the formula I am using:
=IF(Q84>10,7.5*33,IF(Q84<5,7.5*27,IF(AND(Q84>5,Q84<10),7.5*29,0)))

I need 3 different calculations.
If less than 5
if more than 10
If more than 5 and less than 10
than do the calculations.

Instead of using Q84(which is the number of years from today I got using datedif), I would like to use the datedif with the IF statement.

This is the formula I've done myself
=IF(DATEDIF(Q84,TODAY(),"y")>10,7.5*33,IF(AND(Q84>5,Q84<10),7.5*29,0))

I want the second part of the formula to include the datedif instead of Q84.

Thank you