Answer:
8.2+/-0.25
= ( 7.95, 8.45) years
the 95% confidence interval (a,b) = (7.95, 8.45) years
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = 8.2 years
Standard deviation r = 1.1 years
Number of samples n = 75
Confidence interval = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
8.2+/-1.96(1.1/√75)
8.2+/-1.96(0.127017059221)
8.2+/-0.248953436074
8.2+/-0.25
= ( 7.95, 8.45)
Therefore the 95% confidence interval (a,b) = (7.95, 8.45) years
The answer would be x=14 because the 70 degree side would be the same as the (5x) degrees side. So you divide 70 by 5 and that’s how you get 14!!!
Hope this helps!!
We know that
The sum of exterior angles of any polygon is 360 degrees.
Each exterior angle of a regular polygon = 360/n
where n is the number of sides.
<span>So
n = 360/20 = 18
</span>
the answer is the option
<span>b.18 </span>
