Lucy had 2380 mℓ more orange juice than Xandra. After Lucy gave Xandra 490 mℓ of orange juice, the ratio of Lucy's orange juice to Xandra's orange juice became 7 : 3. How much orange juice did Lucy have at first? Give your answer in millilitres.
|
Lucy |
Xandra |
Difference |
Before |
1 u + 2380 |
1 u |
2380 |
Change |
- 490 |
+ 490 |
|
After |
1 u + 1890 |
1 u + 490 |
1400 |
Comparing Lucy and Xandra in the end |
7 p |
3 p |
4 p |
Volume of orange juice that Lucy had in the end
= 1 u + 2380 - 490
= 1 u + 1890
Difference in the volume of orange juice between Lucy and Xandra in the end
= 7 p - 3 p
= 4 p
4 p = 1890 - 490
4 p = 1400
1 p = 1400 ÷ 4 = 350
Volume of orange juice that Lucy had at first
= 7 p + 490
= 7 x 350 + 490
= 2450 + 490
= 2940 mℓ
Answer(s): 2940 mℓ