## Basic College Mathematics (9th Edition)

$\frac{150 trees}{1 acre}=\frac{1500 trees}{10 acres}$
We are given that 150 trees is to 1 acre as 1500 trees is to 10 acres. In order to write this as a proportion, we can write both relations as fractions. 150 trees is to 1 acre can be written as $\frac{150 trees}{1 acre}$ 1500 trees is to 10 acres can be written as $\frac{1500 trees}{10 acres}$ Next, we can set both fractions equal to each other, which gives us a proportional relationship. $\frac{150 trees}{1 acre}=\frac{1500 trees}{10 acres}$ Since the units in the numerators and denominators are different, we do not simplify any further.