5.A store had five different lengths of extension cords for sale. Four of the lengths were 9 feet, 10 feet, 12 feet, and 8 feet. The range of the lengths
of all the extension cords was 6 feet. Which could be the length of the fifth
size of extension cords?

Range is the difference between the largest number in a series and the smallest. The problem says the range is 6 feet. So if 12 is the longest, we can subtract 6 from that and see the fifth one is 6 feet long. Another option is to take the 6 (range), and add it to the shortest one we know, 8 feet. 6+8= 14

Your answer is “6 feet or 14 feet”