Answer
$\frac{418}{unknown} = \frac{16}{100}$
Part = 418
Whole= unknown
Percent = 16
Work Step by Step
$\frac{Part}{Whole} = \frac{Percent}{100}$
Now, 418 curtains is 16% of what number of curtains?
i.e. $\frac{418}{unknown} = \frac{16}{100}$