There are 20 vehicles – cars and motorcycles in a parking area. If there are 56 wheels together, how many cars and motorcycles are there?

Solution

Let no of cars = x and no of motorcycles = y
According to our condition
x + y = 20
X = 20 – y (i)
4x + 2y = 56 (ii)
Replacing (i) in (ii) we get
4(20 – y) + 2y = 56
80 – 4y + 2y = 56
-2y = -24
Thus y = 12
Now replacing y = 12 in x + y = 20 we get
x = 8