Question

Suppose that you decide to participate in a charity walkathon to raise money for your cause. Some people decide to donate a fixed amount, while others agree to donate a little money for every mile you walk. Before the event starts, you raised $25, and you have been pledged $1.50 for each mile you walk. The function defined by d(m) = 1.5m + 25 can be used to relate the miles you walk, m, and the amount of money donated to you in dollars, d(m).

Evaluate d(3)

Explain what it means in the context of the problem.

While you were walking, you lost track of the number of miles you had walked. At the end of the event, an organizer tells you that you raised $40 through your walk. How many miles did you walk?

Answer 1

d(3)=$29.5 is the amount of money raised when you walked 3 miles.

You walked 10 miles fo raise $40

Explanation:

The function to model the amount of money raised in the charity walkathon is:

d(m) = 1.5m + 25

Where m is the miles walked.

• Evaluate d(3):

Substituting m=3:

d(3) = 1.5*3 + 25 = 4.5 + 25 = 29.5

This value is the amount of money raised when you walked 3 miles.

• We know you raised $40 but you don't know the number of miles walked

Since we have the function to calculate d(m), and the money raised is known, we have to find the value of m such that this condition is met:

40 = 1.5m + 25

Subtracting 25:

40 - 25 = 1.5m

15 = 1.5m

Dividing by 1.5:

15 / 1.5 = m = 10

It means you walked 10 miles fo raise $40