



 
Hi Katie, I am going to take a question we received a while ago and change the numbers and wording to ask this question.
You want the change in the number of sales which is 25  15 = 10. Thus the dealership sold 10 more cars in the first week of April than it did in the last week of March. But you want to express this change as a percentage of the earlier value. The earlier value was 15 cars so the percentage change is
You might also call this the percentage increase since there was an increase in the number of cars sold. So what if the number decreases? Here is another problem.
Again it is the change, divided by the earlier value and then expressed as a percentage. Thus this time the percentage change is
Hence there was a 10% decrease in sales from the last week in April to the first week in May. I hope this helps,  


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