Multiplication with Fractions

Hello there,
how do i multiply a fraction and a whole number? Example 20% of 50,000.
I had gotten 0.2 using the following:

chk=echo 20 100 | awk `{print $1/$2}`
echo $chk

$chk \* 50000 displays the error: non-numeric expression.

> myv=50000
> myp=.20
> echo "$myv"*"$myp" | bc
10000.00