Question

the ratio of oil to vinger in a certain salad dressing is 8:5 how much oil must be blended with 7liters of vinegar for that recipe

Answer 1

To get the answer we can use propotion
8 oil ---------------5 vinegar
x oil----------------7 vinegar
Crossmultiply now
5x=8*7
5x=56 :5
x=11.2 - its the answer

Answer 2

I think the answer is that 11.2 litres of oil is requires for 7litres of vinegar