Cylinder H and Cylinder J have a total amount of 1582 mℓ of water. For Cylinder J and Cylinder K, the total amount of water is 2817 mℓ. The amount of water in Cylinder H is ³₈ the amount of water in Cylinder K. What is the average amount of water in the 3 cylinders?
Cylinder H = 3 u
Cylinder K = 8 u 

Cylinder J + Cylinder H = 1582 --- (1)
Cylinder J + Cylinder K = 2817 --- (2)

(2) - (1)
(Cylinder J + Cylinder H) - (Cylinder J + Cylinder K) = 2817 - 1582
8 u - 3 u = 1235
5 u = 1235

1 u = 1235 ÷ 5 = 247
Cylinder H = 3 u = 247 x 3 = 741

Cylinder H + Cylinder J + Cylinder K = 741 + 2817 = 3558 mℓ

Average amount of water in the 3 cylinders
= 3558 ÷ 3 
= 1186 mℓ

Answer(s): 1186 mℓ