The main question in this problem is "find the cost of renting a bike for 5 days"
Step One , determine the cost rates/fees :
It costs $30 to rent a bike, After you rent the bike it's $10 for each day you keep the bike. Step Two , Create an equation :
C = cost , D = days
We rent the bike , so that's $30c and we keep it for 5 more days, that's 10*5 because it's $10 a day. 10c * 5d = $50c. _________________________________________________________
Let's go back to the original question :
"Find the cost of renting a bike for 5 days."
The cost in total for renting the bike for 5 days is $50 + $30 because of the renting fee so it's $80.
I really hope that this helps you out a lot , have a wonderful day!