Respuesta :
Answer:
a) We can be 95% sure that true average age (in weeks) at which babies begin to crawl is between 30.65 weeks and 32.89 weeks.
b) Margin of error for the confidence interval is 1.12 weeks.
Step-by-step explanation:
Let m be the estimate of the average age (in weeks) at which babies begin to crawl
Let ME be the margin of error.
- Lower bound of the confidence interval is m-ME (32.89 weeks)
- Upper bound of the confidence interval is m+ME (30.65 weeks)
then the difference between the upper bound and the lower bound gives:
m+ME - (m-ME) = 2ME = 32.89-30.65=2.24 which gives
ME=1.12 weeks
The confidence interval depicts that we are 95% sure that the true average age when babies begin to crawl is from 30.65 weeks and 32.89 weeks.
What is confidence interval?
The confidence interval simply means a range of estimates for an unknown parameter, which is defined as an interval with a lower bound and an upper bound.
Here, the margin of error for the confidence interval is 1.12 weeks. The lower bound of the confidence interval is 32.89 weeks and the upper bound of the confidence interval is 30.65 weeks.
Then the difference will be:
= 32.89-30.65 = 2.24
The margin of error will now be:
= 2.24/2
= 1.12
Learn more about confidence interval on:
https://brainly.com/question/15712887