Question

Part I. A New Bike and Skateboard Problem

Uncle Eddie asked McKenna and Lara to order 108 new wheels for the 42

skateboards and bicycles in his repair shop. How many bicycles and how

many skateboards are in Uncle Eddie's shop?

Answer 1

Number of bicycles = 30

Number of skateboards = 12

Explanation:

Let the number of bicycles = x

Let number of skateboards = y

It is given that there are total bicycles and skateboards = 42

∴ x + y = 42 ........(1)

Now a bicycle has two tires and a skateboard has four tires, this gives an equation :

2x + 4y = 108 .......(2) (Since uncle Eddie asks to order 108 tires)

Therefore, solving equation (1) and (2), we get

2(x+y=42)

2x+4y=108

2x+2y = 84

- (2x+4y = 108)

- 4 y = - 24

or 4 y = 24

or y = 12

Now substituting the value of y in equation (1),

x + 12 = 42

x = 42 -12

x = 30

So number of bicycles = x =30

And number of skateboards = y = 12