$\"\"$

19.8 is compared the 36. So, 19.8 is the part and 36 is the whole.

$\"\"$ (Percent proportion)

$\"\"$

Apply cross multiplication property: $\"\"$ , when $\"\"$ .

$\"\"$

$\"\"$ (Multiply: $\"\"$ ) $\"\"$

$\"\"$ (Divide each side by 36)

$\"\"$ (Cancel common terms)

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

The 19.8 is $\"\"$ of 36.