Question

The US Mint charges $25 for a limited edition coin, plus a $6 shipping charge. The
cost, c, of purchasing n coins can be found using the function c = 25n+6. There is a
limit of 5 coins per purchase. What is a reasonable domain for this function?
a. {5}
b. {1, 2, 3, 4, 5}
c. {25, 50, 75, 100, 125}
d. {31, 56, 81, 106, 131}

Answer 1

• c=25n+6

So the limit is of 5 coins

Remember that domain is set of n values

So here n can be

• 1,2,3,4,5

Domain is

• {1,2,3,4,5}

Answer 2

Answer:

b. {1, 2, 3, 4, 5}

Step-by-step explanation:

Given function:  

c = 25n + 6

(where c is the total purchase cost and n is the number of coins)

Domain:  input values → n-values

If there is a limit of 5 coins per purchase, this means that you can purchase up to and including 5 coins at any one time.  

Therefore, the domain is:  {1, 2, 3, 4, 5}