Answer:
They should use 1.2 gallons of yellow paint.
Step-by-step explanation:
Given:
Julia and Rasheed are mixing yellow paint and blue paint to make green paint.
The mixture needs to be 60% blue paint and 40% yellow paint.
They need to make 3 gallons of the green paint.
Now, to find the quantity of yellow paint they should use.
As,
60% + 40% = 100%
So, we get the ratio of blue paint to yellow paint:
[tex]60:40[/tex]
= [tex]\frac{60}{40}[/tex]
= [tex]\frac{3}{2}[/tex]
= [tex]3:2.[/tex]
Thus, the ratio of blue paint : yellow paint is 3:2.
They need to make total 3 gallons of green paint.
Now, to get the quantity of yellow paint:
[tex]\frac{2}{5}\ of\ 3\ gallons[/tex]
[tex]=\frac{2}{5} \times 3[/tex]
[tex]=\frac{6}{5}[/tex]
[tex]=1.2\ gallons.[/tex]
Therefore, they should use 1.2 gallons of yellow paint.