To get the 25% of how much Lucindas' family pays
You can either quickly
Multiply the $9,900 by 25%
Or the long way
Multiply the $9,900 by 75% and then subtract $9,900 by the "percent"
Fast Way
9,900*0.25 = $2,475 (Divide the 25% by 100 to get 0.25)
Long Way
9,900*0.75 = $7,425 (Divide the 75% by 100 to get 0.75)
Then subtract
9,900 - 7,425 = 2,475
Either Way
You get $2,475
-IronWolfX