Question 5 ( 7 points)
a. The following stem-and-leaf plot shows the exam result for Applied Statistics course:
Stem(tens)
2
3
4
5
6
7
8
9
Leaf
1
2
0035
000111222
678
99
i. What is the distribution
ii. Compute the sample mean, median and variance using R. Submit the
computer input and output.
b. One of the leading dot-com companies has found that 26% of customers who come
into its web site actually make a purchase of less than $150 and 14% of customers make
a purchase of at least $400. In a sample of 200 customers who come into its web site,
what is the probability that at most 87% of them make a purchase of less than $400?
Perform the computation using R. Submit your computer input and output.