The figure is not drawn to scale. Tank A measuring 49 cm by 42 cm by 25 cm contained 13.77 ℓ of water. Tank B measuring 40 cm by 29 cm by 33 cm contained 29 ℓ of water. Oliver poured some water from Tank A into Tank B without spilling and the water level of Tank B rose to 28 cm. What was the height of water level left in Tank A?
1 ℓ = 1000 cm³
29 ℓ = 29000 cm³
13.77 ℓ = 13.77 x 1000 = 13770 cm³

Height of water in Tank B at first
= 29000 ÷ 40 ÷ 29
= 25 cm

Increase in the height of water in Tank B
= 28 - 25
= 3 cm

Volume of water poured into Tank B
= 40 x 29 x 3
= 3480 cm³ 

Volume of water left in Tank A
= 13770 - 3480
= 10290 cm³ 

Height of water left in Tank A
= 10290 ÷ 49 ÷ 42
= 5 cm

Answer(s): 5 cm