A certain paint is to be mixed with 3 parts yellow to 2 parts blue. Twelve gallons of mixed paint are needed.

How many gallons of blue must be used?

Yes, both ways have the same answer : )

To find out how many gallons of blue paint must be used, we first need to understand the ratio of yellow to blue, which is 3:2. This means that for every 3 parts of yellow paint, we need 2 parts of blue paint.

Since we have 12 gallons of mixed paint that needs to be made, we can set up a proportion to solve for the amount of blue paint:
3 parts yellow / 2 parts blue = 12 gallons / x gallons

To cross multiply, we can rewrite the equation as:
3x = 2 * 12

Simplifying the equation:
3x = 24

Now, divide both sides of the equation by 3 to isolate x:
x = 24 / 3 = 8

Therefore, 8 gallons of blue paint must be used.

This is a proportional reasoning question.

The proportion is blue/total paint=blue/total paint
so the question gave you
2blue/(5 total from 2blue+3yellow) and you are asked How many blue for 12 gallons.
So 2/5=BLUE/12
(12)[2/5]=12[Blue/12]
and solve : )

X gal. of blue.

3x/2 = 1.5x gal. of yel.

x + 1.5x = 12.