Emily had 2300 mℓ more milk than Nora. After Emily gave Nora 430 mℓ of milk, the ratio of Emily's milk to Nora's milk became 7 : 3. How much milk did Emily have at first? Give your answer in millilitres.
|
Emily |
Nora |
Difference |
Before |
1 u + 2300 |
1 u |
2300 |
Change |
- 430 |
+ 430 |
|
After |
1 u + 1870 |
1 u + 430 |
1440 |
Comparing Emily and Nora in the end |
7 p |
3 p |
4 p |
Volume of milk that Emily had in the end
= 1 u + 2300 - 430
= 1 u + 1870
Difference in the volume of milk between Emily and Nora in the end
= 7 p - 3 p
= 4 p
4 p = 1870 - 430
4 p = 1440
1 p = 1440 ÷ 4 = 360
Volume of milk that Emily had at first
= 7 p + 430
= 7 x 360 + 430
= 2520 + 430
= 2950 mℓ
Answer(s): 2950 mℓ