Shiyun had 1680 mℓ more milk than Betty. After Shiyun gave Betty 510 mℓ of milk, the ratio of Shiyun's milk to Betty's milk became 5 : 3. How much milk did Shiyun have at first? Give your answer in millilitres.
| |
Shiyun |
Betty |
Difference |
| Before |
1 u + 1680 |
1 u |
1680 |
| Change |
- 510 |
+ 510 |
|
| After |
1 u + 1170 |
1 u + 510 |
660 |
Comparing Shiyun and
Betty in the end |
5 p |
3 p |
2 p |
Volume of milk that Shiyun had in the end
= 1 u + 1680 - 510
= 1 u + 1170
Difference in the volume of milk between Shiyun and Betty in the end
= 5 p - 3 p
= 2 p
2 p = 1170 - 510
2 p = 660
1 p = 660 ÷ 2 = 330
Volume of milk that Shiyun had at first
= 5 p + 510
= 5 x 330 + 510
= 1650 + 510
= 2160 mℓ
Answer(s): 2160 mℓ
