Answer:
A straight horizontal line, with no slope, across the graph at 15 on the y-axis
Step-by-step explanation:
y = 5(3)
y = 15
Answer:
A sample size of 385 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 
.
That is z with a pvalue of 
, so Z = 1.96.
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.
You feel that a reasonable estimate of the standard deviation is 10.0 hours.
This means that 
What sample size is needed so that the expected margin of error of your estimate is not larger than one hour for 95% confidence?
A sample size of n is needed. n is found when M = 1. So
Rounding up:
A sample size of 385 is needed.
Sounds that you have several answer choices. If that's the case, you need to share those choices. All of them are probably inequalities.
<span>If you would like to
know how many of each did Jan buy, you can calculate this
using the following two equations:
b ... the number of books
m ... the number of magazines
$16 = b * $3 + m * $2.50 ... 16 = 3 * b + 2.50 * m
b + m = 6 ... b = 6 - m
__________________
</span>16 = 3 * b + 2.50 * m
<span>16 = 3 * (6 - m) + 2.50 * m</span>
16 = 3 * 6 - 3 * m + 2.50 * m
16 - 18 = - 3 * m + 2.50 * m
- 2 = - 0.50 * m /0.50
m = 2 / 0.50
m = 4 magazines
<span>b = 6 - m = 6 - 4 = 2 books</span>
Result: Jan bought 4 magazines and 2 books.
