<em>There can be many ways to find the number.</em><em> I have found the number with the help of fractions and multiplication. </em><em>Below is the solution to your problem.</em>
80 = 20/100
=> 5 x 80 = 20 x 5/100
=> 400
<h3><u>Conclusion:</u></h3>
<em>Hence, 80 is 20% of 400. </em><em>I hope my method helped you.</em>