Answer:
And we can conclude that the true mean for the scores are given by this interval (28.37; 30.63) at 90% of confidence
Step-by-step explanation:
Information given
represent the sample mean
population mean
s= 5.2 represent the sample standard deviation
n=59 represent the sample size
Confidence interval
The confidence interval for the true mean is given by the following formula:
(1)
The degrees of freedom are given by:
The Confidence interval is 0.90 or 90%, the significance is
and
, and the critical value is
Now we have everything in order to replace into formula (1):
And we can conclude that the true mean for the scores are given by this interval (28.37; 30.63) at 90% of confidence
Answer:
10.25
Step-by-step explanation:
Answer:
Surface Area = 157 in^2
Step-by-step explanation:
Surface area is the area of each side added together.
Front = Trapezoid = <u>b1 + b2</u> * h <u> 5 + 9 </u> * 5 = 27.5
2 2
Back = Trapezoid = <u>b1 + b2</u> * h <u> 5 + 9 </u> * 5 = 27.5 27.5
2 2 27.5
Right = Rectangle = l * w 6.4 * 5 = 32 32
Left = Rectangle = l * w 5 * 5 = 25 25
Bottom = Rectangle = l * w 9 * 5 = 45 45
Top = Rectangle = l * w 5 * 5 = 25 <u> 25 </u>
157 in^2
He has 30 students in his class because 40% of the class is boys and there is 2.5 40% in 100% so we do 12 x 2.5