The Dugout, Don's Basement, Cd Corner, Harry's Deli, Bill's Software,
Anne's Footwear, and Joanne's House cleaning.
The gift certificates are each in multiples of $5. There is a $100 range in the value of the gift certificates, which start at $25. The mean value of all seven gift certificates is $80, and the median and mode are both $70.
The certificate from The Dugout is worth the most and the one from Joanne House cleaning is worth the least.
The total value of the gift certificates from CD Corner, Harry's Deli, and Anne's Footwear is $270, but Anne's Footwear certificate is worth $50 more than the one from Harry's Deli. The Cd Corner gift certificate is equivalent to the mean for this group of three.
What is the value of the gift certificates from each store?
Middle school level
I would keep track of the information by drawing a line and placing what I know of the values of the gift certificates on the line. First from the statement
I also know that
The mean of the values of the seven gift certificates is $80 so the total of the seven values is 7 x $80 = $560. You have five of the values already on the line so if you can dertemine the value of one more, then the fact that the total is $560 will allow you to find the value of the seventh. You know that