Barrel S and Barrel T had some oil in the ratio 7 : 4. After 40 litres of oil was transferred from Barrel S to Barrel T, the volume of oil in Barrel T became 2 times as much as in Barrel S. How much oil were there in the two barrels in all?
| |
Barrel S |
Barrel T |
Total |
Before |
7x3 =
21 u |
4x3 =
12 u |
11x3 =
33 u |
| Change |
- 40 |
+ 40 |
|
After |
1x11 =
11 u |
2x11 =
22 u |
3x11 =
33 u |
The total volume of oil in the barrels remained unchanged. Make the total volume at first and in the end the same. LCM of 3 and 11 is 33.
Amount of oil transferred from Barrel S to Barrel T
= 21 u - 11 u
= 10 u
10 u = 40
1 u = 40 ÷ 10 = 4
Total volume of oil in two barrels
= 33 u
= 33 x 4
= 132 ℓ
Answer(s): 132 ℓ
