Notice that the dimensions of the region that need to be seeded are given in feet, but the area that one bag of seed can cover is given in square yards.
We will need the conversion between square yards and square feet.
1yard is3feet
⇓
1square yard is3^2=9square feet
Once we have this conversion, we can express in square feet the area one bag of seed can cover.
25* 9=225square feet
To find out how many bags we need we need to know the area, which is the product of the width and length.
80*40=3200square feet
The quotient of these two numbers gives the number of bags we need.
3200/225=14.2
This means that we need a bit more than 14 bags, so we need to purchase 15 bags of seed.
