you fill your car with 15 gallons of gas at a cost of $45. using fractional notation how do you write a proportion that shows how much 5 galloons of gas will cost . use x to represent the unknown cost

Answer 1

Let's denote the unknown cost as x. The given information tells us that filling the car with 15 gallons of gas costs $45.

We can set up a proportion using fractional notation to find the cost of 5 gallons of gas:

(15 gallons)/( $45) = (5 gallons)/(x)

To solve for x, we can cross-multiply:

15 * x = 5 * $45

15x = $225

Finally, we solve for x by dividing both sides of the equation by 15:

x = $225 / 15

x = $15

Therefore, 5 gallons of gas will cost $15.