Answer:
30
Step-by-step explanation:
The mean is the average. Add all the numbers together, then divide by the quantity of numbers in the data set.
1040 / 13 = 80
The mean is 80
w= width
l = 3w
P = 2(l+w)
substitute
24 = 2(3w+w)
24 = 2(4w)
24 =8w
3 =w
The width is 3 inches
the length is 9 inches