The expression which shows the total cost is 2.50+0.4x and the cost of riding 20 miles is $10.50.
Given a taxi charges $2.50 for the first mile and $0.40 for each mile
We are required to make an expression showing total cost and total cost of a 20 mile ride.
let the miles ride by tax be x.
Total cost of the product or service=Number of units*price of one units.
We have been given that $2.50 is fixed so we will not multiply our variable charge with $2.50 and multiply 0.40 with x.
So,the expression showing looks like 2.50+0.40x.
Now to find the cost when taxi travels 20 miles, we have to put x=20,
Cost=2.50+0.40*20
=2.50+(40*20)/100
=2.50+800/100
=2.50+8
=$10.50
Hence the expression which shows the total cost is 2.50+0.4x and the cost of riding 20 miles is $10.50.
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