How much sand was removed from each container? Give your answer in kilograms.

Question

Container X contained 1200 g of sand. Container Y contained 7.2 kg of sand. After an equal amount of sand was removed from each container, Container Y now has 7 times as much sand as Container X. How much sand was removed from each container? Give your answer in kilograms.

Answer 1

X has 1.2 kg to start and 1.2 - x after some is removed

Y has 7.2 to start and 7.2 - x after removal

 

Y is 7x as big as X : 7(1.2 - x) = 7.2 - x

8.4 - 7x = 7.2 - x

Subtract 7.2 from each side

1.2 = 6x

x = .2

 

You should now plug in this answer to the original problem and make sure it makes sense.