To join a local spare dancing group , Jan has to pay a $100 registration fee plus $20 per month. How many months she dance for $400?

Question

HELP ME!!!! I´M DYING HERE

Answer 1

Hi Shawn:

We need to set up a cost function in terms 

of number of months.

 

Letting m= number of months:

cost = 20m + 100

 

we want that to total $400 so

20m + 100 = 400

subtract 100 from both sides

20m = 300

divide both sides by 20

m = 300/20 = 15 months

 

Questions?