Question

Navin signed up for a gym membership. The cost was $125 plus $20 each

month.

a) State the initial value and what it represents in this situation.

b) State the rate of change and what it represents in this situation.

c) State the type of relation.

d) Describe the rate of change (constant or not constant). Explain your
answer.

e) State whether the relation is an example of partial or direct variation.

Answer 1

Explanation:

a. The initial value (cost) of $125 is paid up front. It only provides the right to pay $20 each month the gym is used.

b. The rate of change (from $125) is $20/month. It is the monthly cost of membership.

c. Total cost = $125 + $20x, where x is the number of months you are a active member.

d. The rate of change is a constant $30/month.

e. It is direct variation. The more months, the more it costs at a fixed rate of $20/month.