Answer
$0.8$
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, reworded, $\quad 2\%$ of ($y=40$) is ($x=?$).
Translated:$\quad 0.02\cdot 40=x$
($ 2\%$ converted to decimal notation is $0.02)$
$x=0.8$