From Chapter 3) You are given the following information about a sample dataset.

Question

From Chapter 3) You are given the following information about a sample dataset. It is symmetric. Its mean is 72 and its standard deviation is 18. The size of the sample is 1800. Answer the following questions about the dataset. (2 points each) What do you expect the value of the median to be? what do you expect the value of the 50th%-ile to be? Outliers on the low end will be less than what number? How many of these do you expect? Outliers on the high end will be above what number? How many of these do you expect? How many data points do you expect to be below 54? How many between 54 and 90 How many above 90?

Explanation / Answer

Solutiona:

For symmetric distribution

mean=median

median=72

Soutionb:

Z=0 for 50 th percentile

Z=x-mean/sd

0=x-72/18

x-72=0

X=72

50 th percentile=72

how many datapoints below 54

P(X<54)

Z=x-mean/sd

(Z<54-72/16)

P(z<-1.125)

=1-P(Z<1.125)

=1-0.8708

p =0.1292

ANSWER:

np=1800*0.1292=232.56=233

so 233 data points are below 54

Related Questions

Navigate

• Browse (All)
• Browse F
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.