Question

please solve and show steps.

1. The closing stock price of Ahmadi, Inc. for a sample of 10 trading days is shown below.

Day Stock Price

1 135

2 137

3 144

4 138

5 135

6 139

7 151

8 133

9 232

10 166

For the above sample, compute the following measures.

a. The mean

b. The median

c. The mode

d. The range

2. The flashlight batteries produced by one of the northern manufacturers are known to have an average life of 60 hours with a standard deviation of 4 hours. Please use Chebyshev’s theorem to answer the following questions.

a.

At least what percentage of flashlights will have a life of 54 to 66 hours?

b.

At least what percentage of the batteries will have a life of 52 to 68 hours?

3. The following observations are given for two variables.

Y X

8 12

16 8

15 10

10 11

12 7

Based on the data above, please compute the following measures:

(1) Sample mean for X and Y

(2) Standard deviation for X and Y. (Please give detailed computation steps. Please don’t just give an answer from Excel functions or calculator functions. Otherwise, you will not get all the points.) ​

Answer 1

1. The closing stock price of Ahmadi, Inc. for a sample of 10 trading days is shown below.

Day Stock Price

1 135

2 137

3 144

4 138

5 135

6 139

7 151

8 133

9 232

10 166

For the above sample, compute the following measures.

a. The mean

b. The median

c. The mode

d. The range

a)

b)

Median is the average of the middle two values when it is in increasing order.

133

135

135

137

138

139

144

151

166

232

c)

Mode = 135

d)

Range = Maximum - Minimum = 232 - 133 = 99