Proportional Relationships Quick Check You fill your car with 15 gallons of gas at a cost of $45Using fractional notation, how do you write a proportion that shows how much 5 gallons of gas will cost? Use to represent the unknown cost point)

Question

Proportional Relationships Quick Check You fill your car with 15 gallons of gas at a cost of $45Using fractional notation, how do you write a proportion that shows how much 5 gallons of gas will cost? Use to represent the unknown cost point)

Answer 1

Let x represent the unknown cost for 5 gallons of gas.

We can write the proportion as:

15/45 = 5/x

Now, cross multiply:

15x = 45*5
15x = 225

Divide both sides by 15 to solve for x:

x = 225/15
x = 15

Therefore, 5 gallons of gas will cost $15.