The figure is not drawn to scale. Tank X measuring 50 cm by 44 cm by 15 cm contained 28.4 ℓ of water. Tank Y measuring 40 cm by 25 cm by 32 cm contained 15 ℓ of water. Tim poured some water from Tank X into Tank Y without spilling and the water level of Tank Y rose to 28 cm. What was the height of water level left in Tank X?
1 ℓ = 1000 cm³
15 ℓ = 15000 cm³
28.4 ℓ = 28.4 x 1000 = 28400 cm³

Height of water in Tank Y at first
= 15000 ÷ 40 ÷ 25
= 15 cm

Increase in the height of water in Tank Y
= 28 - 15
= 13 cm

Volume of water poured into Tank Y
= 40 x 25 x 13
= 13000 cm³ 

Volume of water left in Tank X
= 28400 - 13000
= 15400 cm³ 

Height of water left in Tank X
= 15400 ÷ 50 ÷ 44
= 7 cm

Answer(s): 7 cm