How many greeting card?

Question

A store charges $32 to print 80 greeting cards and $0.33 for each additional greeting card.

 

Part A: write an equation to find the total cost, t, of 80 greeting cards and, c, additional cards

 

 

Part B: Use the equation you wrote in part a to find the total cost of 90 greeting cards

Answer 1

The equation has a fixed cost of $32 for 80 cards, plus $0.33 for each additional card.  The fixed cost is called the constant term because it stays the same regardless of how many cards are printed.  The $0.33 is a linear multiplier on the number of additional cards that are printed.  So the equation for the cost in dollars is 

 

t = 0.33*c + 32  

 

To find the cost of 90 greeting cards, note that 90 is 10 more than 80 so there are c = 10 additional cards.  Plug 10 in for c to get 

 

t = 0.33*(10) + 32 = 3.3 + 32 = 35.2 which is $35.20