Question 605695
Percentage is given as 'the part divided by the whole .. times 100'

In this case, you are told the 'part equals 2m'. The whole is given by 'n+3'. And that both m and n are positive. 

So let's plug in the terms
{{{(Part/Whole) * 100}}}
{{{(2m/(n+3)) * 100}}}