A cylindrical dispenser of capacity 5.7 ℓ was filled with pear juice to its brim. The pear juice in the dispenser was then dispensed into a cubical container of sides 20 cm, through a tap flowing at a rate of 452 mℓ /min. After 11 min, the tap was turned off and the container was ⁴₅ full.

1. What percentage of the pear juice in the cylindrical dispenser was left? Round off your answer to the nearest 2 decimal places.
2. How many litres of pear juice were there in the container at first? (1 ℓ = 1000 cm³)

(a)
Volume of pear juice that was dispensed
= 452 x 11
= 4972 mℓ

1 ℓ = 1000 mℓ
4.972 ℓ = 4972 mℓ

Volume of pear juice Left in the dispenser
= 5.7 - 4.972
= 0.728 ℓ

Percentage of pear juice Left in the dispenser
= 0.728 ÷ 5.7 x 100
= 12.771929824561%
≈ 12.77% (to 2 decimal places)

(b)
Amount of pear juice in the container in the end
= ⁴₅ x 20 x 20 x 20
= 6400 cm³

Amount of pear juice in the container at first
= 6400 - 4972
= 1428 cm³

1000 cm³ = 1  ℓ
1428 cm³ = 1.428 ℓ

Answer(s): (a) 12.77%; (b) 1.428 ℓ