The figure is not drawn to scale. Tank S measuring 55 cm by 46 cm by 25 cm contained 20.18 ℓ of water. Tank T measuring 40 cm by 25 cm by 35 cm contained 25 ℓ of water. Japheth poured some water from Tank S into Tank T without spilling and the water level of Tank T rose to 30 cm. What was the height of water level left in Tank S?
1 ℓ = 1000 cm³
25 ℓ = 25000 cm³
20.18 ℓ = 20.18 x 1000 = 20180 cm³

Height of water in Tank T at first
= 25000 ÷ 40 ÷ 25
= 25 cm

Increase in the height of water in Tank T
= 30 - 25
= 5 cm

Volume of water poured into Tank T
= 40 x 25 x 5
= 5000 cm³ 

Volume of water left in Tank S
= 20180 - 5000
= 15180 cm³ 

Height of water left in Tank S
= 15180 ÷ 55 ÷ 46
= 6 cm

Answer(s): 6 cm