I am trying to write this in excel can someone help me with this. I have
tried the if and but no success.

The criteria are as follows.

Handicaps. 3 scores are used with the oldest score dropping
out when the new round is played. 90% of a gross handicap between 0 -
10 for the net; 85% of 11 - 20; 80% of 21 - 30 and lastly 75% of 31 -
40.