Question

If 20% of all manually filed returns contain errors, and 0.05% of all electronically filed returns contain errors, how much more likely is a manual filer to make an error than an electronic filer?​

Answer 1

It would 400x more likely

Answer 2

400 times more likely.

Explanation:

Converting the percents to fractions

20% = 20/100 = 0.2

0.05% = 0.05/100 = 0.0005

So required likely hood = 0.2 / 0.0005

= 400.