An automatics air freshener releases droplets into the air to improve the smell of a living room. At 30 minutes, the canister ha
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Answer:
The margin of error for this estimate is of 14.79 yards per game.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
T interval
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 20 - 1 = 19
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 19 degrees of freedom(y-axis) and a confidence level of . So we have T = 2.093
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
You randomly select 20 games and see that the average yards per game is 273.7 with a standard deviation of 31.64 yards.
This means that
What is the margin of error for this estimate?
The margin of error for this estimate is of 14.79 yards per game.
Answer:
a) P=0.03
b) α=0.05
c) 0.72
d) 100
e) 0.72
Step-by-step explanation:
a) The P-value is the probability of the sample result. In this case the P-value is 0.03.
b) The level of significance is the threshold of probabilty for the null hypothesis to be reejcted or not. It is contrasted with the P-value to know if the effect is significant. In this case, the level of significance is 0.05.
NOTE: if it is a two-side test, the level of significance is 0.1 (two times 0.05).
c) The sample proportion is the one that results from the sample data. In this case, the sample proportion is 0.72.
d) The sample size is the amount of consumers reported. In this case is 100 customers.
e) The null value is 0.72 (equal to the sample proportion), because it is tested if there is no difference between the population proportion and the sample proportion.