The figure is not drawn to scale. Tank N measuring 50 cm by 41 cm by 24 cm contained 18.35 ℓ of water. Tank P measuring 40 cm by 25 cm by 33 cm contained 24 ℓ of water. Valen poured some water from Tank N into Tank P without spilling and the water level of Tank P rose to 28 cm. What was the height of water level left in Tank N?
1 ℓ = 1000 cm³
24 ℓ = 24000 cm³
18.35 ℓ = 18.35 x 1000 = 18350 cm³

Height of water in Tank P at first
= 24000 ÷ 40 ÷ 25
= 24 cm

Increase in the height of water in Tank P
= 28 - 24
= 4 cm

Volume of water poured into Tank P
= 40 x 25 x 4
= 4000 cm³ 

Volume of water left in Tank N
= 18350 - 4000
= 14350 cm³ 

Height of water left in Tank N
= 14350 ÷ 50 ÷ 41
= 7 cm

Answer(s): 7 cm