The figure is not drawn to scale. Tank X measuring 50 cm by 41 cm by 25 cm contained 17.44 ℓ of water. Tank Y measuring 40 cm by 26 cm by 32 cm contained 26 ℓ of water. Harry poured some water from Tank X into Tank Y without spilling and the water level of Tank Y rose to 26 cm. What was the height of water level left in Tank X?
1 ℓ = 1000 cm³
26 ℓ = 26000 cm³
17.44 ℓ = 17.44 x 1000 = 17440 cm³

Height of water in Tank Y at first
= 26000 ÷ 40 ÷ 26
= 25 cm

Increase in the height of water in Tank Y
= 26 - 25
= 1 cm

Volume of water poured into Tank Y
= 40 x 26 x 1
= 1040 cm³ 

Volume of water left in Tank X
= 17440 - 1040
= 16400 cm³ 

Height of water left in Tank X
= 16400 ÷ 50 ÷ 41
= 8 cm

Answer(s): 8 cm