Cylinder B and Cylinder C have a total amount of 1247 mℓ of water. For Cylinder C and Cylinder D, the total amount of water is 3597 mℓ. The amount of water in Cylinder B is ³₅ the amount of water in Cylinder D. What is the average amount of water in the 3 cylinders?
Cylinder B = 3 u
Cylinder D = 5 u 

Cylinder C + Cylinder B = 1247 --- (1)
Cylinder C + Cylinder D = 3597 --- (2)

(2) - (1)
(Cylinder C + Cylinder B) - (Cylinder C + Cylinder D) = 3597 - 1247
5 u - 3 u = 2350
2 u = 2350

1 u = 2350 ÷ 2 = 1175
Cylinder B = 3 u = 1175 x 3 = 3525

Cylinder B + Cylinder C + Cylinder D = 3525 + 3597 = 7122 mℓ

Average amount of water in the 3 cylinders
= 7122 ÷ 3 
= 2374 mℓ

Answer(s): 2374 mℓ