Answer:
I'm guessing the question asks us what is the current balance of the dress after 7 weeks.
So it if drops by 10% every week, we need to find how much it went down one week;
consider 10% as 10/100 in fraction form;
10/100 x 150 = $15, it goes down by $15 each week, but we need to find how much 7 weeks would be:
7 x $15 = $105, it went down $105 so we need to subtract that from the total:
150 - 105 = $45, it would now be currently up for sale for $45.
