Question 563634
All twenty parking spaces in my favorite parking lot are filled. Some spaces are occupied bye motorcycles and others bye cars. Some people count to ten when they get angry, but that was not nearly enough for me. I counted wheels 66 to be exact. How many cars and how many motorcycles had invaded my territory?
===============================
Let m = the number of motorcycles
Then the number of cars = 20 - m [since there are 20 parking spaces]
The number of wheels is given by
N = 66 = 2m + 4c [since motorcycles have 2 wheels, cars have 4]
66 = 2m + 4(20-m)
Solve for m:
66 = 2m + 80 - 4m
2m = 14
m = 7
So there are 7 motorcycles and 13 cars