Dana had 2080 mℓ more milk than Kimberly. After Dana gave Kimberly 440 mℓ of milk, the ratio of Dana's milk to Kimberly's milk became 7 : 3. How much milk did Dana have at first? Give your answer in millilitres.
|
Dana |
Kimberly |
Difference |
Before |
1 u + 2080 |
1 u |
2080 |
Change |
- 440 |
+ 440 |
|
After |
1 u + 1640 |
1 u + 440 |
1200 |
Comparing Dana and Kimberly in the end |
7 p |
3 p |
4 p |
Volume of milk that Dana had in the end
= 1 u + 2080 - 440
= 1 u + 1640
Difference in the volume of milk between Dana and Kimberly in the end
= 7 p - 3 p
= 4 p
4 p = 1640 - 440
4 p = 1200
1 p = 1200 ÷ 4 = 300
Volume of milk that Dana had at first
= 7 p + 440
= 7 x 300 + 440
= 2100 + 440
= 2540 mℓ
Answer(s): 2540 mℓ