$\"\"$ $\"\"$

In the percent proportion, the ratio of a part of something (part) to

the whole (base) is equal to the percent written as a fraction.

$\"\"$

The part $\"\"$

The base $\"\"$

Replace $\"\"$ with 18 and $\"\"$ with 60.

$\"\"$

$\"\"$ $\"\"$ (Apply cross products property)

$\"\"$ (Divide each side by 60)

$\"\"$ (Cancel common terms)

$\"\"$ (Divide: $\"\"$ ) $\"\"$

Eighteen is $\"\"$ of 60.