The figure is not drawn to scale. Tank Z measuring 48 cm by 42 cm by 25 cm contained 18.48 ℓ of water. Tank A measuring 40 cm by 35 cm by 37 cm contained 35 ℓ of water. Xavier poured some water from Tank Z into Tank A without spilling and the water level of Tank A rose to 31 cm. What was the height of water level left in Tank Z?
1 ℓ = 1000 cm³
35 ℓ = 35000 cm³
18.48 ℓ = 18.48 x 1000 = 18480 cm³

Height of water in Tank A at first
= 35000 ÷ 40 ÷ 35
= 25 cm

Increase in the height of water in Tank A
= 31 - 25
= 6 cm

Volume of water poured into Tank A
= 40 x 35 x 6
= 8400 cm³ 

Volume of water left in Tank Z
= 18480 - 8400
= 10080 cm³ 

Height of water left in Tank Z
= 10080 ÷ 48 ÷ 42
= 5 cm

Answer(s): 5 cm