In 1993, 90 houses were built. in 1997, 102 more houses were built. find the average rate of change in the number of new homes built. express the result in terms of new houses built per year.

a. 1/3
b. 102/90
c. 3/1
d. 5/2

could you explain it too? i don't really get how to set it up.

2 answers

change in number of houses built / change in time
= 12/4 = 3 houses per year

I suppose 3/1 would match that.
oh, i got it now thanks