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.
Step-by-step explanation:
= 3 - 5
= -2
line in the picture
No,because your supposed to multiply it by the same number.
2 cups of flour x cups of flour
–––––––––––– = –––––––––––––
24 cookies 54 cookies
cross multiply
2*54=24x
24x=108
x=4.5
4.5 cups of flour
X + y = 24
x - y = 2
Adding both equations
2x = 26
x = 13
y = 11