Question

An orchard has enough space to plant 21 rows with y trees in each row, or 18 rows with y+7 trees in each row. If each orchard plan contains the same number of trees, how many trees can each orchard contain?

*I know the answer is 882 trees. But, I have no idea how to set up the problem so that I can solve it. Please help. Thank you.

Answer 1

since (21)(y) is the same as 18(y+7) , let's say so:

21y = 18(y+7)
21y = 18y + 126
3y = 126
y = 42

so ......

Answer 2

Thank you!

21y

21 X 42= 882

I get it! Thank you!