3.0 NOT SURE IF ITS CORRECT
780 (or c)
I think this is correct because 4 x 5 = 20 x 5 = 100 and 100 x 5 = 500
500 + 280 = ????
780
6^5 = 6•6•6•6•6
x^7 = x•x•x•x•x•x•x
x^5 = x•x•x•x•x
5^6 = 5•5•5•5•5•5
Answer:
a) 
b) The should sample at least 293 small claims.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so
, which means that the answer of question a is z = 1.645.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
(b) If the group wants their estimate to have a maximum error of $12, how many small claims should they sample?
They should sample at least n small claims, in which n is found when
. So







The should sample at least 293 small claims.