Answer:
21.75 years (Almost 22 years)
21 years and 9 months. :)
Step-by-step explanation:
There are 12 months in a year.
261/12 = 21.75
.75 = 3/4
3/4(12) = 9 months
Hope that helps!
Answer:
C.
Step-by-step explanation:
Answer:
Here is a summary of the Boston Marathon completion times for two years.
Year
Mean (minutes)
Standard deviation (minutes)
Number of runners
2012
263
50
21,576
31,984
2014
243
52
A sports journalist takes separate random samples of 35 runners from each year. Then they look at the
difference in the mean completion time sampled from each year 2012 - 2014).
What do we know about the shape of the sampling distribution of D2012 22014, and why?Step-by-step explanation:
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