The figure is not drawn to scale. Tank B measuring 48 cm by 45 cm by 25 cm contained 12.12 ℓ of water. Tank C measuring 40 cm by 29 cm by 34 cm contained 29 ℓ of water. Tommy poured some water from Tank B into Tank C without spilling and the water level of Tank C rose to 28 cm. What was the height of water level left in Tank B?
1 ℓ = 1000 cm³
29 ℓ = 29000 cm³
12.12 ℓ = 12.12 x 1000 = 12120 cm³

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

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

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

Volume of water left in Tank B
= 12120 - 3480
= 8640 cm³ 

Height of water left in Tank B
= 8640 ÷ 48 ÷ 45
= 4 cm

Answer(s): 4 cm