The figure is not drawn to scale. Tank N measuring 50 cm by 45 cm by 20 cm contained 18.9 ℓ of water. Tank P measuring 44 cm by 25 cm by 33 cm contained 22 ℓ of water. Owen poured some water from Tank N into Tank P without spilling and the water level of Tank P rose to 29 cm. What was the height of water level left in Tank N?
1 ℓ = 1000 cm³
22 ℓ = 22000 cm³
18.9 ℓ = 18.9 x 1000 = 18900 cm³

Height of water in Tank P at first
= 22000 ÷ 44 ÷ 25
= 20 cm

Increase in the height of water in Tank P
= 29 - 20
= 9 cm

Volume of water poured into Tank P
= 44 x 25 x 9
= 9900 cm³ 

Volume of water left in Tank N
= 18900 - 9900
= 9000 cm³ 

Height of water left in Tank N
= 9000 ÷ 50 ÷ 45
= 4 cm

Answer(s): 4 cm