1. 1.6 Tables and Graphs GOAL 1 Use tables to organize data. GOAL 2 Use graphs to organize real-life data, such as the amounts of various foods consumed (Example 2). What you should learn To help you see relationships among real-life data, such as the average cost of making a movie. Why you should learn it

2. GOAL 1 USING TABLES TO ORGANIZE DATA Remember: A table is just one way to organize data. We need to organize it to make it easier to understand. EXAMPLE 1 1.6 Tables and Graphs

3. Extra Example 1 The data in the table represents the number of worldwide shipments of personal computers, in millions. During which 2-year period did the number of shipments increase the most? Solution: PC Shipments (millions) Year’90’92’94’96’98 PCs23.732.447.970.898.4 Find the difference in each 2-year period. The greatest increase in shipments occurred from 1996-1998. Change ----8.715.522.927.6

4. GOAL 2 USING GRAPHS TO ORGANIZE DATA BAR GRAPHS—The bars may be either vertical or horizontal. 1.6 Tables and Graphs EXAMPLE 2 LINE GRAPHS—Connect the data points with straight lines; do not draw curves.

5. A graph for the data in Extra Example 1 is shown. Is the graph misleading? Explain. PC Shipments (millions) Year’90’92’94’96’98 PCs23.732.447.970.898.4 Extra Example 2 The bar graph is not misleading since the vertical scale is consistent.

6. Drawing Graphs All graphs need: 1. Title 2. Axis labels 3. Appropriate scale Does it go beyond the largest number? Does it show the differences in data? 4. Consistent scale 5. Neatness

7. The data in the table represents the number of households in the U.S. in millions. Checkpoint Year’60’70’80’90’00 No.52.863.480.893.3103.2 a.During which 10-year period did the number of households increase the most? 1970 to 1980 b. Draw a bar graph to represent the data.

8. Checkpoint (cont.) Year’60’70’80’90’00 No.52.863.480.893.3103.2 EXAMPLE 3 TITLE LABELS SCALE

9. Extra Example 3 Year’60’70’80’90’00 No.17.421.427.834.339.0 The data in the table represents the number of people over age 65 in the U.S. in millions. a.Draw a line graph.

10. Extra Example 3 (cont.) Year’60’70’80’90’00 No.17.421.427.834.339.0 b. During which 10-yr period was there the least increase? Answer: from 1960 – 1970. Think: How does the bar graph show the answer to this question? The steeper the line, the greater the difference between the points.

11. Checkpoint a. Draw a line graph for the data in Extra Example 1. PC Shipments (millions) Year’90’92’94’96’98 PCs23.732.447.970.898.4 b. During which two-year period did the number of shipments increase the least? 1990-1992

12. QUESTIONS?