Question

If a phone card is used to make a long distance phone call, you are charged $0.50 per call plus an additional $0.31 per minute. Part A: Write an equation that can be used to find the total cost of a phone call that lasts for m minutes. Part B: Shalon was charged $5.15 after using a phone card to make a phone call. For how many minutes did he talk on the phone? Show your work.

Answer 1

Part A: c for cost. c=0.31m+0.5

0.31m is the cost per minute. 0.5 is cost per call.

Part B: 0.31m+0.5=5.15 to solve we must rearrange.

subtract 0.5 from each side giving us 0.31m=4.85

divide by 0.31 giving us m=15.65