Question

In: Statistics and Probability

The reading speed of second grade students is approximately normal with a mean of 90 words...

The reading speed of second grade students is approximately normal with a mean of 90 words per minutes and standard deviation of 10 words per minute. A sample off 55 second graders were selected

a) what is the mean (center) of the sampling distribution for x?

b) What is the spread (standard deviation)of the sampling distribution of x?

Solutions

Expert Solution

a)

Mean of sampling distribution of sample mean = = 90

b)

Standard deviation of sampling distribution of sample mean = / sqrt(n)

= 10 / sqrt(55)

= 1.3484


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