Answer:
Confidence Interval in 95% confidence level for the quality rating is (6.06,7.46)
Step-by-step explanation:
Confidence Interval can be calculated using the formula M±ME where
- M is the mean of the sample
- ME is the margin of error in a given confidence level
Using the sample obtained from 50 business travelers we get
- Mean of the sample is 6.76
- standard deviation of the sample is 2.526
Margin of error (ME) around the mean using the formula
ME=
where
- z is the corresponding statistic in 95% confidence level (1.96)
- s is the standard deviation of the sample (2.526)
- N is the sample size (50)
Using the numbers in the formula we get:
ME=
≈ 0.70
Then the confidence interval becomes 6.76±0.70
Answer:
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0 1 2 (3) 4 5 6 7 8 9 10
Answer: There is not a good prediction for the height of the tree when it is 100 years old because the prediction given by the trend line produced by the regression calculator probably is not valid that far in the future.
Step-by-step explanation:
Years since tree was planted (x) - - - - height (y)
2 - - - - 17
3 - - - - 25
5 - - - 42
6 - - - - 47
7 - - - 54
9 - - - 69
Using a regression calculator :
The height of tree can be modeled by the equation : ŷ = 7.36X + 3.08
With y being the predicted variable; 7.36 being the slope and 3.08 as the intercept.
X is the independent variable which is used in calculating the value of y.
Predicted height when years since tree was planted(x) = 100
ŷ = 7.36X + 3.08
ŷ = 7.36(100) + 3.08
y = 736 + 3.08
y = 739.08
Forward prediction of 100 years produced by the trendline would probably give an invalid value because the trendline only models a range of 9 years prediction. However, a linear regression equation isn't the best for making prediction that far in into the future.
The area of the square is 9, the area of all the semi circles added together is 15.7, when you add them together you get 24.7
