Andrew has 2 tanks. Tank S and Tank T are of different capacities. If Tank S is filled by a tap at a rate of 5 litres per minute and Tank T is filled by a tap at a rate of 6 litres per minute, when Tank S is completely filled, 8 litres of water flowed out from Tank T. If Tank S is filled by a tap at a rate of 6 litres per minute and Tank T is filled by a tap at a rate of 2 litres per minute, when Tank S is completely filled, Tank T is only half-filled. What is the capacity of Tank T? Express your answer in litres.

	Scenario 1		Scenario 2
Tank type	Tank S	Tank T	Tank S	Tank T
Volume of the tank	5 u	6 u - 8	6 p	2 p x 2 = 4 p

Let 1 u be the time taken for Scenario 1.
Let 1 p be the time taken for Scenario 2.

5 u = 6 p --- (1)
6 u - 8 = 4 p
6 u = 4 p + 8 --- (2)

Make u the same.

(1) x 6
30 u = 36 p --- (3)

(2) x 5
30 u = 20 p + 40 --- (4)

(3) = (4)
36 p = 20 p + 40
36 p - 20 p = 40
16 p = 40
1 p = 40 ÷ 16 = 2.5

Volume of Tank T
= 4 p
= 4 x 2.5
= 10 ℓ

Answer(s): 10 ℓ