Answer:
8 tricycles
Step-by-step explanation:
Make a system of equations
Let t represent tricycles, and b represent bicycles
We know that tricycles have 3 wheels, bicycles have 2, and there are a total of 64 wheels
We also know each has one rider, and there are a total of 28 riders
3t+2b=64
t+b=28
Subtract t from both sides in the second equation. This will allow us to use substitution
b= -t+28
Substitute -t+28 in for b in the first equation
3t+2b=64
3t+2(-t+28)=64
Distribute the 2
3t + 2*-t+ 2* 28 =64
3t-2t+56=64
Combine like terms
t+56=64
Subtract 56 from both sides
t=8
There were 8 tricycles