2.2 Homework

1.   Classify the histogram as skewed to the left, skewed to the right, bell-shaped, or approximately uniform.

The histogram is

1. approximately symmetric
   1. bell-shaped
   2. uniform
2. skewed to the left
3. skewed to the right

2. Classify the histogram as skewed to the left, skewed to the right, bell-shaped, or approximately uniform.

The histogram is

1. approximately symmetric
   1. bell-shaped
   2. uniform
2. skewed to the left
3. skewed to the right

3.  Classify the histogram as unimodal or bimodal.

The histogram is  ______

4.   Classify the histogram as unimodal or bimodal.

The histogram is ________

5,   Movies: A sample of people were asked how many movies they had seen in a movie theater during the past month. Following is a frequency histogram of their responses.

(a)What is the most frequent number of movies seen?

(b)How many people were in the sample?

(c)How many people saw fewer than one movie?

(d)What percentage of the people saw more than one movie?

6.  Forty nine rats were trained to run a maze. The following frequency histogram presents the number of trials it took each rat to learn the maze.

(a) What is the least frequent number of trials?

(b) How many rats learned the maze in three trials or less?

(c) How many rats took seven trials or more to learn the maze?

7.  Cough, cough: The following table presents the number of days a sample of patients reported a cough lasting from an acute cough illness.

(a) Construct a frequency histogram.

Click the line on the horizontal axis above the numbers and drag the bar to the correct frequency.

(b) Construct a relative frequency histogram.

Click the line on the horizontal axis above the numbers and drag the bar to the correct frequency.

(c) Are the histograms skewed to the left, skewed to the right, or approximately symmetric?

The histograms are  _____