Answer:
The architects can be 95% confident that the mean breaking strength of the white wood is within this interval (149.736 , 1.664)
Step-by-step explanation:
Given
Sample = n = 16
x = 75.7
s = 10.9
First we Calculate the degree of freedom.
Degree of freedom is calculated as
df = (n - 1)t
df = (16 - 1)t
df = 15t
The we check the t-table corresponding value for 0.05
t 0.05= 1.75377.
0.05 is gotten from
(100% - 95%) = 5%= 5/100 = 0.05
Calculating the True mean breaking strength through the confidence interval
Solving the confidence interval.
This is given by:
x ± ts√df
Confidence Interval = 75.7 ± 1.75377 * 10.9 * √15
Confidence Interval = 75.7 ± 74.036
Confidence Interval = 75.7 + 74.036 , 75.7 - 74.036
Confidence interval = 149.736 , 1.664
Interpreting the above;
The architects can be 95% confident that the mean breaking strength of the white wood is within this interval (149.736 , 1.664)
