Tiffany had 1720 mℓ more milk than Gem. After Tiffany gave Gem 550 mℓ of milk, the ratio of Tiffany's milk to Gem's milk became 5 : 3. How much milk did Tiffany have at first? Give your answer in millilitres.
|
Tiffany |
Gem |
Difference |
Before |
1 u + 1720 |
1 u |
1720 |
Change |
- 550 |
+ 550 |
|
After |
1 u + 1170 |
1 u + 550 |
620 |
Comparing Tiffany and Gem in the end |
5 p |
3 p |
2 p |
Volume of milk that Tiffany had in the end
= 1 u + 1720 - 550
= 1 u + 1170
Difference in the volume of milk between Tiffany and Gem in the end
= 5 p - 3 p
= 2 p
2 p = 1170 - 550
2 p = 620
1 p = 620 ÷ 2 = 310
Volume of milk that Tiffany had at first
= 5 p + 550
= 5 x 310 + 550
= 1550 + 550
= 2100 mℓ
Answer(s): 2100 mℓ