A car uses 5 gallons of gasoline to travel 97.5 miles. At this rate, how many miles can the car travel using 13 gallons of gasoline?

253.5 miles

Step-by-step explanation:

This problem can be solved by using the concept of "ratios" and "proportions."

Step 1: Check for the "known" and "unknown" variables.

The known variables are: 5 gallons, 97.5 miles and 13 gallons while the unknown variable is the "number of miles" the car can travel using 13 gallons.

Step 2: It's time to plug the values into the proportion.

            =

Step 3: Solve the proportion.

            =  ⇒ 5x = 1,267.5 ⇒ x = 253.5 miles

answer is the third choice:

3x^5+4x^4+x^3+2x^2-10x-7=0

step-by-step explanation: