She would have to make 6,000 dollars in sale because she starts with a 1,400
income and to match the other salary she would make an extra 120 dollars to match the bigger salary, for example:
120 / 0.02 = 6,000
We take 120 the amount extra we need to make and realize our 2% of our sales need to be equivalent to 120. So we divided 120 by 0,02 to find out what makes the cut for having 120 dollar bonus. Hope this helps ^^