Question

Your friend decided to join a bmx course so he can race with his friends. The
courses charges $7 per race after the membership fee. Your friend has raced 28
times and paid a total of $210, including the membership fee. What is the
membership fee? How much would he pay if he races 39 times? *

Answer 1

Answer:

He would pay $287 if he races 39 times

Thus, the membership fee is $14.

Step-by-step explanation:

Linear Modeling

The situation described in the problem can be modeled as the equation of a line which has the form:

$y=ax+b$

Where y is the cost of the course, x is the number of races, a is the cost per race, and b is the membership fee.

We know the course charges $7 per race, so a=7. Since your friend has raced x=28 times and paid y=210, we can find the value of b:

$210=7(28)+b$

Operating:

$210=196+b$

b=14

Thus, the membership fee is $14.

The linear model is now:

$y=7x+14$

If he races x=39 times, your friend would pay:

$y=7(39)+14=287$

y=287

He would pay $287 if he races 39 times