Answer:
8 cookies were left after the bake sale. 72 were sold.
Step-by-step explanation:
64*1.25= 80
80*.9= 72
8
125% of 64 is equal to 80.
90% of 80 is equal to 72.
The number left was 10% of the number he made. The number he made was 125% of 64, so the number left was 8
10% × 125% × 64 = 0.125 × 64 = 8
thats all i could really come up with at the top of my head