Answer
$ 50\%$
Work Step by Step
Typical percentage problem:
What percent ($n$, as a decimal number) of (the base amount $y)$ is $x?$
Translated:$\quad n\cdot y=x$
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Here, What percent ($n$, as a decimal number) of ($y=50$ is ($x=25$)$?$
Translated:$\quad n\cdot 50=25$
... divide with $50$
$ n=0.5\qquad$ .... convert to percent notation,
(move the decimal point two places to the right and write a percent symbol.)
$=50\%$