Cylinder F and Cylinder G have a total amount of 960 mℓ of water. For Cylinder G and Cylinder H, the total amount of water is 2292 mℓ. The amount of water in Cylinder F is ²₅ the amount of water in Cylinder H. What is the average amount of water in the 3 cylinders?
Cylinder F = 2 u
Cylinder H = 5 u 

Cylinder G + Cylinder F = 960 --- (1)
Cylinder G + Cylinder H = 2292 --- (2)

(2) - (1)
(Cylinder G + Cylinder F) - (Cylinder G + Cylinder H) = 2292 - 960
5 u - 2 u = 1332
3 u = 1332

1 u = 1332 ÷ 3 = 444
Cylinder F = 2 u = 444 x 2 = 888

Cylinder F + Cylinder G + Cylinder H = 888 + 2292 = 3180 mℓ

Average amount of water in the 3 cylinders
= 3180 ÷ 3 
= 1060 mℓ

Answer(s): 1060 mℓ