To paint a room, Suzanne uses blue and white paint in the ratio of blue:white = 8:3. What was the total number of gallons of paint used if she used 6 gallons of blue paint?

Sagot :

7 gallons of paint in total

8:3 is the ratio. 8 is blue and 3 is white.
the given 6 is blue and the white paint is not given.

so subtract 8-6 it is equal to 2
so subtract 3-2 the answer is 1

Add 6 and 1 together an that is the answer


Fraction is a ratio of two numbers.  Therefore we have to find a fraction equivalent to 8:3 or 8/3.

Solution:

8:3 = 6:x

Multiply the extreme (outer values) and multiply the means (inner values).  In other words, cross multiplication.

(8)(x) = (3)(6)
8x = 18
8x/8 = 18/8 or 9/4
x = 2 ²/₈  or  2 ¹/₄

2 ¹/₄ gallons is used for white paint if 6 gallons is used for blue paint to satisfy the ration blue is white = 8 :3.

Add the number of gallons:
6 gallons (for blue) + 2 ¹/₄ gallons (for white) = 8 ¹/4 gallons

ANSWER: The total number of gallons used to paint the room is 8 ¹/4
 gallons.

Check:
8/3 = 6/2 ¹/₄
(3)(6) = (8) (2 ¹/4)
18 = (8)(9/4)
18 = (2)(9)
18 = 18