The salesperson earn $172 in commission last week. how much money, in dollars, did he have in sales last week? the correct answer is $3,640 ($3,640 is really the answer). explain step-by-step how to come to that answer or show your work.

We know that the total amount of sales last week was $3,640, so 100% of sales is $3,640. We also  know that the commission earned last week is $172, so we need to find what percentage of $3,640 is $172. To do that we are going to establish a proportion as follows:


Now we just solve for :



We can conclude that our sales person has a commission of 4.73% over the total amount of sells per week. Since the commission of the last week was $172, the total sales was $3640 because the 4.73% of $3640 is $172.