Shannon had 2160 mℓ more coffee than Irene. After Shannon gave Irene 570 mℓ of coffee, the ratio of Shannon's coffee to Irene's coffee became 5 : 2. How much coffee did Shannon have at first? Give your answer in millilitres.
| |
Shannon |
Irene |
Difference |
| Before |
1 u + 2160 |
1 u |
2160 |
| Change |
- 570 |
+ 570 |
|
| After |
1 u + 1590 |
1 u + 570 |
1020 |
Comparing Shannon and
Irene in the end |
5 p |
2 p |
3 p |
Volume of coffee that Shannon had in the end
= 1 u + 2160 - 570
= 1 u + 1590
Difference in the volume of coffee between Shannon and Irene in the end
= 5 p - 2 p
= 3 p
3 p = 1590 - 570
3 p = 1020
1 p = 1020 ÷ 3 = 340
Volume of coffee that Shannon had at first
= 5 p + 570
= 5 x 340 + 570
= 1700 + 570
= 2270 mℓ
Answer(s): 2270 mℓ
