The figure is not drawn to scale. Tank W and Tank X have base areas of 4000 cm
2 and 3000 cm
2 respectively. Water was poured into an empty rectangular Tank W until it reached a height of 21 cm. Some of the water was then poured from Tank W into Tank X which contained 2.1 ℓ of water until the height of the water in both tanks were the same.
- Find the new height of the water in Tank W.
- How many litres of water were poured into Tank X?
(a)
Volume of water in Tank W
= 4000 x 21
= 84000 cm
3 (Base area x height)
1 ℓ = 1000 cm
3 2.1 ℓ = 2100 cm
3 Total volume of Tank W and Tank X
= 84000 + 2100
= 86100 cm
3 Total base area of Tank W and Tank X
= 4000 + 3000
= 7000 cm²
Height of Tank W after
= 86100 ÷ 7000
= 12.3 cm
(b)
Volume of water in Tank X after pouring
= 3000 x 12.3
= 36900 cm
3 Volume of water poured into Tank X
= 36900 - 3000
= 33900 cm
3 33900 mℓ = 33.9 ℓ
Answer(s): (a) 12.3 cm; (b) 33.9 ℓ