Answer:
Sam will need 9 liters of blue paint.
and 3 liters of white paint.
Explanation:
Paint is mixed 3 parts blue to 1 part white.
i.e. if 3x liters of blue paint is taken than x liters of white paint is needed.
Sam needs 12 liters of paint.
i.e. 3x+x=12
⇒ 4x=12
Dividing both sides by 4,we get
x=3
Blue paint=3x=3×3=9 liters
White paint=x=3 liters
Hence, Sam will need 9 liters of blue paint.
and 3 liters of white paint.