Charlotte has 2 tanks. Tank V and Tank W are of different capacities. If Tank V is filled by a tap at a rate of 4 litres per minute and Tank W is filled by a tap at a rate of 7 litres per minute, when Tank V is completely filled, 6 litres of water flowed out from Tank W. If Tank V is filled by a tap at a rate of 6 litres per minute and Tank W is filled by a tap at a rate of 2 litres per minute, when Tank V is completely filled, Tank W is only one-fifth-filled. What is the capacity of Tank W? Express your answer in litres.
|
Scenario 1 |
Scenario 2 |
Tank type |
Tank V |
Tank W |
Tank V |
Tank W |
Volume of the tank |
4 u |
7 u - 6 |
6 p |
2 p x 5 = 10 p |
Let 1 u be the time taken for Scenario 1.
Let 1 p be the time taken for Scenario 2.
4 u = 6 p --- (1)
7 u - 6 = 10 p
7 u = 10 p + 6 --- (2)
Make u the same.
(1) x 7
28 u = 42 p --- (3)
(2) x 4
28 u = 40 p + 24 --- (4)
(3) = (4)
42 p = 40 p + 24
42 p - 40 p = 24
2 p = 24
1 p = 24 ÷ 2 = 12
Volume of Tank W
= 10 p
= 10 x 12
= 120 ℓ
Answer(s): 120 ℓ