A girl spent 20% of her pocket money on books she was left with 7200 Naira how much is her pocket money
m = her pocket money
A girl spent 20% of her pocket money on books means:
She spent on books
20% m = 20 / 100 m = 0.2 m
Rest is:
m - 0.2 m = 0.8 m
She was left with 7200 means:
0.8 m = 7200
m = 7200 / 0.8 = 9000