Answer: 2.5 gallons.
Step-by-step explanation:
Given : In order to get a certain shade of blue paint, a mixer must have 5 parts white paint to 3 parts blue.
Total paint mixed = 5+3= 8 parts
The ratio of white paint to the total mixture = [tex]\dfrac{\text{Parts of white colour}}{\text{Total parts of mixture }}[/tex]
[tex]=\dfrac{5}{8}[/tex] (1)
Let x be the number of gallons of white paint.
If 4 gallons of paint must be mixed , then the ratio of white paint to the total mixture = [tex]=\dfrac{x}{4}[/tex] (2)
From (1) and (2) , we have
[tex]\dfrac{x}{4}=\dfrac{5}{8}[/tex]
Multiply 4 on both sides , we get
[tex]x=\dfrac{5}{8}\times4=\dfrac{5}{2}=2.5[/tex]
⇒ x= 2.5
⇒ Number of gallons of white paint is required = 2.5 gallons.
