An equation could be: p/3=4 To solve this equation: p/3*3/1=4*3/1 : p=12 : Paco is 12 years old--you are using what is called "Inverse Operation"!!! (otherwise you could multiply 3*4 to get 12 by reversing operations) I hope this helped you!
If Zack can walk 7.5 blocks in 30 minutes and we are looking for how many blocks he can walk in 1 minute, we will divide 7.5 by 30 as that will be the number of blocks per minute.
.
and 
, you have the equation 
.
.