Answer:= (504, 516)
Therefore, the 90% confidence interval (a,b) = ( 504, 516)
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 gain x = 510
Standard deviation r = 37
Number of samples n = 95
Confidence interval = 90%
z(at 90% confidence) = 1.645
Substituting the values we have;
510+/-1.645(37/√95)
510+/-1.645(3.796)
510+/-6.24
510+/-6
= (504, 516)
Therefore at 90% confidence interval (a,b) = ( 504, 516)