Pail C and Pail D had some oil in the ratio 9 : 4. After 42 litres of oil was transferred from Pail C to Pail D, the volume of oil in Pail D became 2 times as much as in Pail C. How much oil were there in the two pails in all?
| |
Pail C |
Pail D |
Total |
Before |
9x3 =
27 u |
4x3 =
12 u |
13x3 =
39 u |
| Change |
- 42 |
+ 42 |
|
After |
1x13 =
13 u |
2x13 =
26 u |
3x13 =
39 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 3 and 13 is 39.
Amount of oil transferred from Pail C to Pail D
= 27 u - 13 u
= 14 u
14 u = 42
1 u = 42 ÷ 14 = 3
Total volume of oil in two pails
= 39 u
= 39 x 3
= 117 ℓ
Answer(s): 117 ℓ
