This formula sits inside a small summary table with percentile values in column F and gender values in G4 and H4.
Working from the inside out, the IF function is set up like this:
Here, each value in the gender column is tested against the value in G4, "Male".
The result is an array of boolean values like this:
Only scores associated with males make it into the array, female scores are translated to FALSE. This array goes into the PERCENTILE function with the k value from F5, 90%.
PERCENTILE automatically ignores FALSE values and returns a result of 86.8.
The reference to Gender in G$4 is locked to prevent the row from changing. The reference to k values, $F5 is locked to prevent the column from changing. As a result, the formula can be copied across the range G5:H7.