A 9 foot roll of aluminium foil costs 3.87. What is the price per yard

1.29 a yard

Step-by-step explanation:

there are 3 feet in each yard so 9 divide by 3 would be 3 yards

then you take 3.87 and divided it by 3 you get 1.29 per yard

if you want to check then you just multiply 1.29 times 3 = 3.87