Grace spends half her time practicing her drums, and 3 of the remaining 4
time on homework and dinner after school one afternoon. She spends the
remaining 3 hour reading. How long does she practice the drums
I hope you meant "3/4 of the remaining time"
Don't you read what you post?
Anyway, now we have time spent is
1/2 + 3/4 * 1/2 = 7/8 of her time. So
1/8 x = 3
x = 24 hours at first
so she drummed for 12 hours