Additional Review for Chapter 1 Test

Algebra Name______CHAPTER 1 DATA EXPLORATION Period ______Date ______Additional Review for Chapter 1 Test

Match each term on the left with its definition or description.

_F__1. Median A. A graph that is used to show a five number summary.

_C__2. Mode B. The sum of all the numbers in a data set divided by the number of data items in the set. _G__3. Bar Graph C. The data item that occurs most often.

_I__4. Histogram D. The difference between the upper quartile and the lower quartile. _H__5. Scatter Plot E. The difference between the maximum and minimum number in a data set. _A__6. Box Plot F. The middle number in a set of ordered data.

_B__7. Mean G. A type of graph used for categorical variables.

_J__8. Outlier H. A type of graph used to graph two variables.

_D__9. Interquartile Range I. A type of graph that groups numerical data.

_E__10. Range J. A data item that lies outside the normal pattern of the graph.

11. Fill in each blank with always, sometimes, or never to make a true statement. Justify your answers. a) Data sets ___ sometimes ___ have outliers.

A value must be 1.5 times IQR < the 1st quartile or 1.5 times IQR > the 3rd quartile.

b) The median of a data set is ___ sometimes ___ a value in the data set.

If there is an even set of numbers in the data, the median is the mean of the two middle numbers.

c) A scatter plot ___never___ involves only one variable.

Scatter plots have two variables.

d) A mode is ___ sometimes ___ an outlier.

In the set 1,2,3,4,5,6,7,25,25 the median is 5, Q1=2.5, Q3 = 16; 16X1.5=24, 25>24, therefore even though 25 is the mode, it is also considered an outlier.

e) The median of a data set that includes only whole numbers is ___sometimes___ a whole number.

The median of the set 2,3,4,5 is 3.5. 11. A movie theater recorded the number of tickets sold for two movies each day during one week. Box plots of the data are shown below.

Based on the box plot, determine whether each of the following statements is true, false, or cannot be determined from the information given in the box plot. Justify your answers.

a) The mean number of tickets sold for Movie X is greater than the mean number of tickets sold for Movie Y.

Cannot be determined because you are given the median, Q1 and Q2, not the frequency.

b) The median number of tickets sold for Movie X is greater than the median number of tickets sold for Movie Y.

True; Movie X has a median of about 620 and the median of Movie Y is about 580.

c) The interquartile range of the number of tickets sold for Movie X is greater than the interquartile range of the number of tickets sold for Movie Y.

True; Movie X has an interquartile range of about 750 – 510 ≈ 190. Movie Y has an interquartile range of about 610 - 530 ≈ 80.

d) The total number of tickets sold for Movie Y was bigger than the total number of tickets sold for Movie X. Cannot be determined using the box and whisker plot because we do not know the number of tickets sold for either movie.