Name: ______Block: ______Date: ______

7.4 Building Histograms from Frequency Tables & Stem-and-Leaf Plots

A ______ is a type of bar graph used to display numerical data that have been organized

into ______intervals. To make a histogram from a frequency table, use the following steps.

Step 1 Draw and label a ______and a ______axis. Include a title.

Step 2 Show the intervals from the frequency table on the horizontal axis. To find the interval, divide the range by # of intervals you wish to use. Use the quotient to determine the interval size.

Step 3 For each interval on the horizontal axis, draw a bar whose height is given by the ______.

1-2. The list gives the year of birth for each state governor in the US in 2007. Choose intervals and make a frequency table. Then construct a histogram to represent the data.

Interval / Tally / Frequency / Cumulative Frequency

______

3. This stem-and-leaf plot represents the numbers of cupcakes sold by students during a fundraiser. Construct a histogram that could represent the same set of data.

Cupcakes Sold

Stem / Leaf
0 / 4 4 7 8
1 / 0 0 2 3 6 6
2 / 1 5 9
3 / 0 1 2 3 5 7 8


For exercises 4 -8, use the histogram at the right,

4.  How large is each interval?

5.  What percent of the runners ran slower than 74 seconds?

6.  What was the most likely time?

7.  What was the greatest time?

8.  Which statement can be concluded from the histogram?

a)  The least time for 400-meter dash is 60 seconds.

b)  The greatest time for 400-meter dash is 84 seconds.

c)  The biggest group ran the 400-meter dash in the interval 70-74 seconds.

d)  The biggest group ran the 400-meter dash in the interval 60-64 seconds.

For exercises 9-12, use the histograms below.

9.  Which city has the tallest building? ______

10.  Determine which city has more buildings that are 800-899 feet tall. ______

11.  (a)Determine which city has more buildings that are at least 600 feet tall. ______

(b) What percent of the buildings in that city are at least 600 feet tall?

12.  What is the height of the shortest building in each city? ______

HOMEWORK 7.4

For Exercises 1–3, use the histogram below that shows data about scores on a history test.

1. How many students scored at least 81 on the test?

2. How many students scored less than 81 on the exam?

3. Can you determine the highest grade from the histogram? Explain.

4. The frequency table shows the average points per game

for all NBA teams for a recent season.

Draw a histogram to represent the set of data. ______

Review! Can you solve these correctly?

5. What is the new price of a $48 jacket, which is marked down 15%?

6. Suppose the height of a rectangular prism is doubled. Find the ratio of the volume of the new prism to the volume of the old prism.

7. A soup can has a diameter of 8 cm and the height of 6 cm. Calculate the amount of metal that was used to make the can.