Pail F and Pail G had some oil in the ratio 7 : 5. After 40 litres of oil was transferred from Pail F to Pail G, the volume of oil in Pail G became 3 times as much as in Pail F. How much oil were there in the two pails in all?
| |
Pail F |
Pail G |
Total |
Before |
7x1 =
7 u |
5x1 =
5 u |
12x1 =
12 u |
| Change |
- 40 |
+ 40 |
|
After |
1x3 =
3 u |
3x3 =
9 u |
4x3 =
12 u |
The total volume of oil in the pails remained unchanged. Make the total volume at first and in the end the same. LCM of 4 and 12 is 12.
Amount of oil transferred from Pail F to Pail G
= 7 u - 3 u
= 4 u
4 u = 40
1 u = 40 ÷ 4 = 10
Total volume of oil in two pails
= 12 u
= 12 x 10
= 120 ℓ
Answer(s): 120 ℓ
