The figure shows a container made up of 3 sections. Cuboid R with a square base of side 4 cm and height 40 cm. Cube S with a side of 12 cm. Cuboid T that is 73 cm by 26 cm by 44 cm. Water from a tap above flows down at a rate of 2.4 litres per minute while water is drained out from the bottom at a rate of 2 litre per minute. How long did it take to fill up the container to a height of 70 cm from the base? Give the answer in minutes correct to nearest whole number.
Volume of S
= 12 x 12 x 12
= 1728 cm³ 

Volume of T
= 73 x 26 x 44
= 83512 cm³ 

2 ℓ = 2000 cm³ 
2.4 ℓ = 2400 cm³ 

Net increase in volume per minute
= 2400 - 2000
= 400 cm³/min

Height of R to be filled with water
= 70 - (44 + 12)
= 14 cm

Volume of water in R
= 4 x 4 x 14
= 224 cm³ 

Volume of water in T, S and part of R
= 83512 + 1728 + 224
= 85464 cm³ 

Time taken to reach height
= 85464 ÷ 400
≈ 214 min (Correct to nearest whole number)

Answer(s): 214 min