Answer:
The survey results will be inaccurate since the entire sample of the population was eating at the same restaurant.
Step-by-step explanation:
When doing a survey you must make sure it is unbiased by asking a variety of people for example if you are wondering what is the favorite class at school you have to ask a certain amount of people from each class because if you ask only people from P.E the answer more than likely will be P.E or if u ask 3 people from Art and 17 from P.E your answer will properly be P.E. Make sense?
You would take 175 and multiply it by 0.20 which is 35. The you would subtract 35 from 175 because it is marked down so you would get 140. Next, you would take 140 and multiply it by 0.10 and get 14. Finally subtract 14 from 140 to get your answer which would be $126.
Answer:
half of 7.4 is 3.7 so the houses are 3.7 miles apart.
Answer:
99% confidence interval for the population average examination score is between a lower limit of 69.2872 and an upper limit of 82.7128.
Step-by-step explanation:
Confidence interval = mean +/- margin of error (E)
mean = 76
variance = 144
sd = sqrt(variance) = sqrt(144) = 12
n = 25
degree of freedom (df) = n - 1 = 25 - 1 = 24
confidence level (C) = 99% = 0.99
significance level = 1 - C = 1 - 0.99 = 0.01 = 1%
t-value corresponding to 24 df and 1% significance level is 2.797
E = t×sd/√n = 2.797×12/√25 = 6.7128
Lower limit = mean - E = 76 - 6.7128 = 69.2872
Upper limit = mean + E = 76 + 6.7128 = 82.7128
99% confidence interval is (69.2872, 82.7128)
