Answer:
The standard deviation is 2.6832815729997
Step-by-step explanation:
SD^2=(12-12)^2+...+(14-12)^2/10
SD^2=72/10
SD^2=7.2
SD=squeare root of 7.2
SD=2.6832815729997
To find the surface area of the cube using the formula, you would substitute in 2 1/2 for the length of the side.
SA = 6 x 2.5 x 2.5
SA = 37.5 ft.²
You are finding the area of one face (2.5 x 2.5) and multiplying it by six because there are six groups of this.
Answer:
Margin of error for a 95% of confidence intervals is 0.261
Step-by-step explanation:
<u>Step1:-</u>
Sample n = 81 business students over a one-week period.
Given the population standard deviation is 1.2 hours
Confidence level of significance = 0.95
Zₐ = 1.96
Margin of error (M.E) = 
Given n=81 , σ =1.2 and Zₐ = 1.96
<u>Step2:-</u>
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On calculating , we get
Margin of error = 0.261
<u>Conclusion:-</u>
Margin of error for a 95% of confidence intervals is 0.261
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