A. 63
B. 171
C.25
D. 12
This should be right I believe?<span />
Answer:
29.5+/-1.11
= ( 28.39, 30.61)
Therefore, the 90% confidence interval (a,b) =( 28.39, 30.61)
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 = 29.5
Standard deviation r = 5.2
Number of samples n = 59
Confidence interval = 90%
z-value (at 90% confidence) = 1.645
Substituting the values we have;
29.5+/-1.645(5.2/√59)
29.5+/-1.645(0.676982337100)
29.5+/-1.113635944529
29.5+/-1.11
= ( 28.39, 30.61)
Therefore, the 90% confidence interval (a,b) =( 28.39, 30.61)
