Answer:
(3.442 ; 6.558)
Step-by-step explanation:
Given :
Mean score after patient is given the magnet treatment :
Mean score, xbar = 5
Standard deviation, s = 2.4
Sample size, n = 20
The confidence interval :
Mean ± margin of error
Margin of Error = Tcritical * standard error
The critical value at 95%, df = 20 - 1 = 19
Tcritical = 2.093 (T-student distribution)
The standard error = s/√n = 2.4 / √20 = 0.5367
The margin of error = 2.903 * 0.5367 = 1.558
The confidence interval :
Xbar ± Margin of error
5 ± 1.558
(3.442 ; 6.558)
