Natalie had 1680 mℓ more orange juice than Diana. After Natalie gave Diana 400 mℓ of orange juice, the ratio of Natalie's orange juice to Diana's orange juice became 7 : 3. How much orange juice did Natalie have at first? Give your answer in millilitres.
|
Natalie |
Diana |
Difference |
Before |
1 u + 1680 |
1 u |
1680 |
Change |
- 400 |
+ 400 |
|
After |
1 u + 1280 |
1 u + 400 |
880 |
Comparing Natalie and Diana in the end |
7 p |
3 p |
4 p |
Volume of orange juice that Natalie had in the end
= 1 u + 1680 - 400
= 1 u + 1280
Difference in the volume of orange juice between Natalie and Diana in the end
= 7 p - 3 p
= 4 p
4 p = 1280 - 400
4 p = 880
1 p = 880 ÷ 4 = 220
Volume of orange juice that Natalie had at first
= 7 p + 400
= 7 x 220 + 400
= 1540 + 400
= 1940 mℓ
Answer(s): 1940 mℓ