Raeann had 2180 mℓ more coffee than Shiyun. After Raeann gave Shiyun 570 mℓ of coffee, the ratio of Raeann's coffee to Shiyun's coffee became 7 : 3. How much coffee did Raeann have at first? Give your answer in millilitres.
|
Raeann |
Shiyun |
Difference |
Before |
1 u + 2180 |
1 u |
2180 |
Change |
- 570 |
+ 570 |
|
After |
1 u + 1610 |
1 u + 570 |
1040 |
Comparing Raeann and Shiyun in the end |
7 p |
3 p |
4 p |
Volume of coffee that Raeann had in the end
= 1 u + 2180 - 570
= 1 u + 1610
Difference in the volume of coffee between Raeann and Shiyun in the end
= 7 p - 3 p
= 4 p
4 p = 1610 - 570
4 p = 1040
1 p = 1040 ÷ 4 = 260
Volume of coffee that Raeann had at first
= 7 p + 570
= 7 x 260 + 570
= 1820 + 570
= 2390 mℓ
Answer(s): 2390 mℓ