Answer:
the domain and range can be found by horizontal and vertical test
Step-by-step explanation:
6.B
7.D
8.A
9.C
500 people took the survey.
12 out of 15 people is 80% of the population. 12/15 = 0.80
Thus, 80% of the population prefers eating in the restaurant.
If 400 represents the people who prefers eating in the restaurant; then, 400 is the 80% of the population. To get the total population or 100%, we must divide 400 by 0.80 or 80%
400 / 0.80 = 500 people.
Out of the 500 people, 400 selected eating in the restaurant while the remaining 20% of the population or 100 people selected cooking at home.
Answer:
At least 547 records need to be studied.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence interval 
, we have the following confidence interval of proportions.
In which
Z is the zscore that has a pvalue of 
.
And the margin of error is:
95% confidence interval
So 
, z is the value of Z that has a pvalue of 
, so 
.
In this problem, we have that:
At least 547 records need to be studied.
