Cindy had 1920 mℓ more coffee than Emma. After Cindy gave Emma 510 mℓ of coffee, the ratio of Cindy's coffee to Emma's coffee became 5 : 2. How much coffee did Cindy have at first? Give your answer in millilitres.
| |
Cindy |
Emma |
Difference |
| Before |
1 u + 1920 |
1 u |
1920 |
| Change |
- 510 |
+ 510 |
|
| After |
1 u + 1410 |
1 u + 510 |
900 |
Comparing Cindy and
Emma in the end |
5 p |
2 p |
3 p |
Volume of coffee that Cindy had in the end
= 1 u + 1920 - 510
= 1 u + 1410
Difference in the volume of coffee between Cindy and Emma in the end
= 5 p - 2 p
= 3 p
3 p = 1410 - 510
3 p = 900
1 p = 900 ÷ 3 = 300
Volume of coffee that Cindy had at first
= 5 p + 510
= 5 x 300 + 510
= 1500 + 510
= 2010 mℓ
Answer(s): 2010 mℓ
