The figure shows a container made up of 3 sections. Cuboid M with a square base of side 9 cm and height 44 cm. Cube N with a side of 11 cm. Cuboid P that is 74 cm by 27 cm by 48 cm. Water from a tap above flows down at a rate of 2.7 litres per minute while water is drained out from the bottom at a rate of 1 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 N
= 11 x 11 x 11
= 1331 cm³ 

Volume of P
= 74 x 27 x 48
= 95904 cm³ 

1 ℓ = 1000 cm³ 
2.7 ℓ = 2700 cm³ 

Net increase in volume per minute
= 2700 - 1000
= 1700 cm³/min

Height of M to be filled with water
= 70 - (48 + 11)
= 11 cm

Volume of water in M
= 9 x 9 x 11
= 891 cm³ 

Volume of water in P, N and part of M
= 95904 + 1331 + 891
= 98126 cm³ 

Time taken to reach height
= 98126 ÷ 1700
≈ 58 min (Correct to nearest whole number)

Answer(s): 58 min