There are 15 bikes and tricycles in a store. There are a total of 36 wheels. How many bikes are in the store?

Question

Word problem

Answer 1

There is another way, suppose tricycle: x (number of tricycles), then bike: 15-x (number of bikes),

a bike has two wheels, a tricycle has three wheels, so we can get a format: 3x + 2(15-x) =36.  then x=6, so 15-6=9(number of bikes)

Answer 2

Let's set up this problem

 

b = # bikes

t = # trikes

 

b + t = 15      total number of bikes

2b + 3t = 36  total number of wheels

 

Using elimination, we want to eliminate one of the variables

 

-2(b+t=15)

-2b-2t=-30

2b+3t=36

 

Add the two equations together

 

t = 6

Then b+t=15

b+6=15

b = 9

 

There are 9 bikes and 6 trikes