Answer:
$169.33
Step-by-step explanation:
Each of the friends spent ...
$14.95 +6.99 +2.25 = $24.19
The seven friends together spent ...
7($24.19) = $169.33
Answer:
A sample size of 79 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of
.
For this problem, we have that:

The margin of error is:
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.09?
A sample size of n is needed.
n is found when M = 0.09. So






Rounding up to the nearest whole number.
A sample size of 79 is needed.
Answer:
B. 
Step-by-step explanation:
Total number of students surveyed = 420
Of which only
prefer rap.
So, the number of people who like rap is the product of the fraction of people who prefer rap and the total number of students.

The number of students that prefer rap is 105
So the equation is
.