3 represents skateboards and 1 represents bikes. We need to get from 3 to 12 and 1 to the answer by using the same number you used to get from 3 to 12.
To get from 3 to 12 you multiply by 4
3*4=12
So let's go ahead and multiply 1 by 4 as well
1*4=4
Your ratio is now 12:4 and 4 stands for bikes so there are 4 bikes
