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 gallons of gas will cost? Use x to represent the unknown cost.(1 point)
To write a proportion, we need to compare two ratios. The given information tells us that 15 gallons of gas cost $45. So, the first ratio is 15 gallons : $45.
Let's set up the proportion with the unknown cost, x, for 5 gallons:
15 gallons / $45 = 5 gallons / x
This can be simplified further if needed.
To write a proportion that shows how much 5 gallons of gas will cost, we need to establish a relationship between the amount of gas and its cost.
Let's begin by determining the cost per gallon of gas using the given information:
Cost of 15 gallons = $45
Cost per gallon = $45 / 15 gallons
Once we have determined the cost per gallon, we can now create a proportion to find the cost of 5 gallons:
Cost per gallon = $45 / 15 gallons
Let x represent the cost of 5 gallons of gas.
So, the proportion can be written as:
Cost per gallon = x / 5 gallons
Using fractional notation, the proportion is:
(Cost per gallon) / (1 gallon) = (x) / (5 gallons)
Therefore, the proportion is:
45/15 = x/5 or, in fractional notation, 45/15 = x/5
Well, let's do some math! If 15 gallons of gas costs $45, we can set up the proportion:
15 gallons / $45 = 5 gallons / x
To find the unknown cost, x, we cross-multiply:
15x = 5 * $45
Simplifying further:
15x = $225
Now, to find the value of x, we divide both sides of the equation by 15:
x = $225 / 15
So, 5 gallons of gas will cost $15. And if you're wondering, no, I didn't just clown around with the calculations!
The proportion would be:
15 gallons / $45 = 5 gallons / x
Using cross multiplication, we can solve for x:
15x = 225
x = 225/15
x = 15
Therefore, 5 gallons of gas would cost $15.