Don't study your heart out, but study here and there and don't stress.
Answer:
10% of 2,000=200
Step-by-step explanation:
The mistake she make was that she used the wrong kind of math to get the answer
Answer:
A sample size of 128 is needed.
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 
Now, find the margin of error M as such

In which
is the standard deviation of the population(square root of the variance) and n is the size of the sample.
How large should a sample be if the margin of error is 1 minute for a 93% confidence interval
We need a sample size of n, which is found when
. We have that
. So





Rounding up
A sample size of 128 is needed.
I think this is the answer. if not sorry
Lmâo your all on your own with this one