Answer:
Part a [5522.3511 ; 5727.8488]
Part b. The p-value is 0.050115.
The H0 is rejected and concluded that the true mean life of a biomedical device is greater than 5500.
Step-by-step explanation:
The 95 % confidence interval for the mean of the population is given by
∝= 1- 0.95= 0.05
υ= n-1= 15-1= 14
x`± t ∝() s / √n
5625.1 ± { t (0.05) (14)} 226.1 / √15
5625.1 ± 1.76 * 226.1/3.8729
5625.1 ± 102.7488
[5522.3511 ; 5727.8488]
Part b
State the null and the alternate hypothesis
H0: u= 5500 against the claim Ha: u > 5500
the test statistic
t= x`- u/ s/ √n
t= 5625.1-5500/226.1 / √15
t=2.143
The p-value is 0.050115.
The result is not significant at p < 0.05.
The H0 is rejected and concluded that the true mean life of a biomedical device is greater than 5500.