Mary had 1790 mℓ more juice than Nora. After Mary gave Nora 490 mℓ of juice, the ratio of Mary's juice to Nora's juice became 5 : 2. How much juice did Mary have at first? Give your answer in millilitres.
| |
Mary |
Nora |
Difference |
| Before |
1 u + 1790 |
1 u |
1790 |
| Change |
- 490 |
+ 490 |
|
| After |
1 u + 1300 |
1 u + 490 |
810 |
Comparing Mary and
Nora in the end |
5 p |
2 p |
3 p |
Volume of juice that Mary had in the end
= 1 u + 1790 - 490
= 1 u + 1300
Difference in the volume of juice between Mary and Nora in the end
= 5 p - 2 p
= 3 p
3 p = 1300 - 490
3 p = 810
1 p = 810 ÷ 3 = 270
Volume of juice that Mary had at first
= 5 p + 490
= 5 x 270 + 490
= 1350 + 490
= 1840 mℓ
Answer(s): 1840 mℓ
