Answer:
For 99% of confidence interval is 67.5±1.3524
Step-by-step explanation:
Given:
Mean height =67.5 inches
Standard deviation:2.1 inches
Z at 99%.
No of samples 16.
To find:
confidence interval
Solution:
We have formula for confidence interval,
=mean ±Z*{standard deviation/sqrt(no.of observation)}
Now
Z=99%
has standard value as ,
Z=2.576
Confidence interval= mean±Z{standard deviation/sqrt(No. of samples)}
=67.5±2.57{(2.1/sqrt(16)}
=67.5±2.576(2.1/4)
=67.5±1.3524
-0.3*0.2*12, multiply -0.3 by 0.2 to get -0.06, now multiply 12 by it to get, -0.72.
