The gym offers a discount when more than one member of the family joins.The first member ( n=10) pays $550 per year. The second member to join (n=1) get discount of $75 per yar. The third member (n=2) gets an additional $75. The price for the nth member is given by 550+(-75n)

a. What is the price for the fourth member to join (n=3)
b. For a large family,is it possible for a member to would join free? If so, which member would it be? Explain you reasoning
c. Other than $0, what is the lowest amount that member would pay to join? Which member would it be? Explain your reasoning



Answer :

a. 550-(3x75)=325
b. The 9th member may join free as 550-(75x8)=-50 and as I imagine the gym will not pay the customer money they should have a free membership but only after the 9th person.
c. $25, 550-(75x7)=25 therefore the 8th person pays $25 for their membership.