Answer
People can identify 36.4% of the words.
Work Step by Step
55000 is the whole. 20000 is the part. The percent is unknown.
$\frac{20000}{55000} = \frac{x}{100}$
$55000x = 20000\times100$
$\frac{55000x}{55000} = \frac{2000000}{55000}$
$x = 36.4$