Answer:
Step-by-step explanation:
The 2:3 ratio has 2+3 = 5 ratio untis. If that total represent 20 litres of paint, then each ratio unit stands for 4 litres of paint. That is, the mixture has
- 8 litres of white paint
- 12 litres of blue paint
Mary wants to make the mixture have the ratio 1:7, so the number of litres of paint will be ...
... 1 white : 7 blue = 8 litres of white : 56 litres of blue
That is, the number of litres of blue paint must increase from 12 to 56, an increase of ...
... 44 litres of blue paint