Answer:
29+/-2.26
= (26.74, 31.26) characters
Therefore the 95% confidence interval (a,b) = (26.74, 31.26) characters
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 characters
Standard deviation r = 6 characters
Number of samples n = 27
Confidence level = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
29+/-1.96(6/√27)
29+/-1.96(1.154700538379)
29+/-2.263213055223
29+/-2.26
= (26.74, 31.26) characters
Therefore the 95% confidence interval (a,b) = (26.74, 31.26) characters
