Emily had 2240 mℓ more coffee than Penelope. After Emily gave Penelope 580 mℓ of coffee, the ratio of Emily's coffee to Penelope's coffee became 5 : 2. How much coffee did Emily have at first? Give your answer in millilitres.
| |
Emily |
Penelope |
Difference |
| Before |
1 u + 2240 |
1 u |
2240 |
| Change |
- 580 |
+ 580 |
|
| After |
1 u + 1660 |
1 u + 580 |
1080 |
Comparing Emily and
Penelope in the end |
5 p |
2 p |
3 p |
Volume of coffee that Emily had in the end
= 1 u + 2240 - 580
= 1 u + 1660
Difference in the volume of coffee between Emily and Penelope in the end
= 5 p - 2 p
= 3 p
3 p = 1660 - 580
3 p = 1080
1 p = 1080 ÷ 3 = 360
Volume of coffee that Emily had at first
= 5 p + 580
= 5 x 360 + 580
= 1800 + 580
= 2380 mℓ
Answer(s): 2380 mℓ
