Chapter 1.2, Problem 49E

(a)

To determine

To Examine: the data and clarify if any answers are suspicious.

Answer to Problem 49E

One female is quite suspicious.

Explanation of Solution

Given:

  

When the students in a large first year college class were asked that how many minutes they studied on a typical weeknight. All of them responded in multiple of 10 minutes because they tried to round-off their response to nearest half an hour. One female has responded with 360 minutes which is quite suspicious and is the outlier in the current data.

(b)

To determine

To make: a back-to-back stemplot and explain whether women study more than men

Answer to Problem 49E

Women	Stem	Men
															0	0	3	3	3	3
													9	6	0	5	6	6	6	8	9	9	9
							2	2	2	2	2	2	2	1	1	0	2	2	2	2	2	2	2
8	8	8	8	8	8	8	8	8	8	7	5	5	5	5	1	5	5	8
												4	4	0	2	0	0	3	4	4
															2
														0	3	0
															3
														6	3

It appears that females study more than men.

Explanation of Solution

Calculation:

The back-to-back stem plot of the data is below:

Leaf unit = 10

Women	Stem	Men
															0	0	3	3	3	3
													9	6	0	5	6	6	6	8	9	9	9
							2	2	2	2	2	2	2	1	1	0	2	2	2	2	2	2	2
8	8	8	8	8	8	8	8	8	8	7	5	5	5	5	1	5	5	8
												4	4	0	2	0	0	3	4	4
															2
														0	3	0
															3
														6	3

10 out of 30 females of the students have responded with 180 minutes and 7 out of 30 males have responded with 120 minutes. The peak of females is higher than that of males.

Conclusion: “Thus, it appears that females study more than men.”