Answer is 1.6 pounds
.02 is not big enough to round up, so round down
Answer: 160 songs.
Step-by-step explanation:
<em>75% hip hop music - 120 songs
</em>
<em>100% all music - x songs
</em>
<em>Let's write the proportion:</em>
<em />
<em />
<em>Thus, Landon have 160 songs in his music library.</em>
Answer:
237.5
Step-by-step explanation:
Answer:
A sample of 18 is required.
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 Z-table as such z has a p-value of
.
That is z with a pvalue of
, so Z = 1.88.
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.
A previous study indicated that the standard deviation was 2.2 days.
This means that 
How large a sample must be selected if the company wants to be 92% confident that the true mean differs from the sample mean by no more than 1 day?
This is n for which M = 1. So



Rounding up:
A sample of 18 is required.