Answer:
44L
Step-by-step explanation:
Mary has 20 liters of paint that have white:blue ratio of 2:3. She wants to make a new mix by adding more blue paint until the ratio becomes 1:7. That means the volume of white paint of the old mid and new mix should be the same.
The volume for the second mix will be:
old mix white paint = new mix white paint
2/(3+2) * 20L = 1/(1+7) * V2
2/5 * 20L= 1/8 V2
8L= 1/8 V2
V2= 8L * 8
V2= 64L
If the new mix volume is 64L and old mix volume is 20L, then the blue paint needed to be added will be: 64L- 20L= 44L