The figure, not drawn to scale, is made of two connected cubical tanks, V and W. Tank V is sealed at the top and completely filled to the brim. Tank W is ⁴₅ filled with 138088 mℓ of water. The height of the water level in Tank W is 3 cm higher than that in Tank V. Height of Tank W is 60 cm. Water is then drained from the container and the height of the water level from the base falls to 23 cm.

1. What is the capacity of Tank W in litres?
2. What is the volume of water in the tank now in litres?

(a)
⁴₅ of Tank W = 138088 mℓ
¹₅ of Tank W = 138088 ÷ 4 = 34522 mℓ
⁵₅ of Tank W = 34522 x 5 = 172610 mℓ

1 ℓ = 1000 mℓ

Capacity of Tank W = 172610 mℓ = 172.61 ℓ

(b)
Fraction of Tank W not filled
= 1 - ⁴₅
= ¹₅

Height of Tank W not filled
= ¹₅ x 60 cm
= 12 cm

Height of Tank V
= 60 - 12 - 3
= 45 cm

Volume of remaining water in Tank V
= 45 x 45 x 23
= 46575 cm³ 

Volume of remaining water in Tank W
= 60 x 60 x 23
= 82800 cm³ 

Total volume of remaining water in the tank
= 46575 + 82800
= 129375 cm³

1 ℓ = 1000 cm³
129375 cm³ = 129.375 ℓ

Answer(s): (a) 172.61 ℓ; (b) 129.375 ℓ