Ed plants trees in city parks. He used 1/10 of a bag of fertilizer around the base of a newly planted tree. How many trees can Ed fertilize with 40 bags of fertilizer

To determine this you could think of it in a couple ways.

1. If it takes 1/10 of a bag of fertilizer to put around 1 tree, he can fertilize 10 trees with 1 bag because there are 10 groups of 1/10 in a bag. Take 10 x 40 because there are 40 bags and get 400 trees to be fertilized.

2. You can divide 40 by 1/10 as the other strategy.

This is the same as 40 x 10/1.

Also equaling 400 trees that can be fertilized.