First you need to find the percent equivalent to that of the ratio. The ratio is 3:5. From there you would take the 3, and divide it by 5. 3/5=0.6. Apply that to the information that you are given: 8(0.6)=4.8.
There are two cups in one pint and there are two pints in one quart. That means that there are four cups in one quart. Three cups would be 3/4 of a quart.