Answer
$0.6$
Work Step by Step
If we can write a fraction so that its denominator is one of 10,100, 1000,...,
we can easily write it as a decimal number
Using the fact that $5\cdot 2=10,$
$\displaystyle \frac{3}{5}=\frac{3\cdot 2}{5\cdot 2}=\frac{6}{10 }$
We write this as a decimal number with one digit after the decimal point:
$= 0.6$