So the following is the answer of the following question in your problem and please do not post to many question in just one posting.
#1 The 98% confidence interval for the mean hours is between 6 and 50.
#2 The smallest margin of error between the two is southern florida with 1.8% margin of error.
So, first, what are the two sides?
let's call then x and y
we know that 2(x+y)=12.5 (that's the distance around)
so that means that x+y=6.25 (I just divided both by 2)
now, x=4y (from "4 times as long as it is wide")
so we can substitute:
x+4x=6.25
5x=6.25
x=1.25
so one side, is 1.25 and the other will be 1.25*4=5
and for the area we multiply the two:
1.25*5=6.25 square kilometers, and this is the answer!
The constant of proportionality is for every 1 x, there is 0.25 y. y = 0.25, and on a graph, x is always the "1." Since x is worth 1, y must be worth 0.25.
The answer for the problems are below in the picture let me know if that makes sense.