Stem-and-Leaf Plots & Histograms Quiz

MULTIPLE CHOICE

1. The number of floors of each building in a particular city is recorded. Make a stem-and-leaf plot of the data.

Number of Floors
24 / 38 / 46 / 16 / 28 / 31 / 12 / 27 / 32 / 49 / 33 / 12 / 38 / 34 / 48 / 22 / 36 / 29 / 47 / 41
49 / 30 / 21 / 17 / 40 / 13 / 32 / 15 / 31 / 21 / 13 / 16 / 43 / 33 / 30 / 25 / 28 / 29 / 13 / 11
a. / Number of Floors

Key: 1 | 1 means 11 / c. / Number of Floors
Key: 1 | 1 means 11
b. / Number of Floors

Key: 1 | 1 means 11 / d. / Number of Floors

Key: 1 | 1 means 11

2. Find the least value, greatest value, mean, median, mode, and range of the data set.

Stems / Leaves
2 / 2 4 8 8 8 9 9
3 / 0 2 2 4 6 6 8
4 / 1 1 4 6
5 / 0 2
a. / least value: 22
greatest value: 52
mean: 33
median: 35
mode: 28
range: 30 / c. / least value: 22
greatest value: 52
mean: 28
median: 30
mode: 33
range: 35
b. / least value: 22
greatest value: 52
mean: 35
median: 33
mode: 28
range: 30 / d. / least value: 0
greatest value: 9
mean: 4.5
median: 3
mode: 8
range: 9

SHORT ANSWER

3.Find the least value, greatest value, mean, median, mode, and range of the data in the stem-and-leaf plot.

Stems / Leaves
6 / 3 6
7 / 2 9
8 / 4 7 7
9 / 0 0 1 1 3 3 3
Key: 6|3 means 63

4. Daniel and 7 of his classmates took the ACT test, a college entrance exam. The student’s test scores were as follows: 26, 28, 32, 19, 23, 24, and 31. Using the data provided, make a stem-and-leaf plot. Explain the steps you used.

5. Use the data in the table to make a stem-and-leaf plot.

Hundreds of Acres Lost in Forest Fires
70 / 45 / 60 / 15 / 20 / 23 / 17
65 / 57 / 48 / 12 / 27 / 101 / 19

MULTIPLE CHOICE

  1. The table shows the scores that 20 students received on a test. Use the data to make a frequency table showing the students scores.

Students Test Scores
75 / 82 / 83 / 90 / 77
93 / 85 / 88 / 72 / 74
81 / 88 / 76 / 79 / 83
86 / 94 / 78 / 82 / 80
a. /
b. /
c. /
d. /

MULTIPLE CHOICE

  1. Use the frequency table to make a histogram.

Number of Sit-ups Students Can Do in 1 Minute
Number / / / / /
Frequency / 10 / 8 / 9 / 6 / 2
a. / / c. /
b. / / d. /

SHORT ANSWER

  1. A student tracks the number of questions on each of her quizzes. The following table shows how many questions were on each quiz.

5 / 9 / 14 / 18 / 16
19 / 7 / 6 / 7 / 3
12 / 10 / 8 / 17 / 17

Based on the information, complete the following frequency table.

Number / 1–5 / 6–10 / 11–15 / 16–20
Frequency
  1. Use the frequency table to make a histogram.

Summer Camp Attendance Last Week
Ages / 0–5 / 6–11 / 12–17 / 18–23
Frequency / 15 / 25 / 17 / 19
  1. Use the frequency table to make a histogram.

Number of Jobs by Age
Age / 16–25 / 26–35 / 36–45 / 46–55 / 56–65
Frequency / 20 / 25 / 31 / 15 / 9

Stem-and-Leaf Plots & Histogram Quiz

Answer Section

MULTIPLE CHOICE

1.ANS:B

Step 1 Group the data by tens digit.

Step 2 Order the data from least to greatest.

Step 3 List the tens digit in the “Stems” column.

Step 4 Record the ones digit of each data point in the “Leaves” column.

Step 5 Title the graph and write a key.

Number of Floors
Stems / Leaves
1 / 1 / 2 / 2 / 3 / 3 / 3 / 5 / 6 / 6 / 7
2 / 1 / 1 / 2 / 4 / 5 / 7 / 8 / 8 / 9 / 9
3 / 0 / 0 / 1 / 1 / 2 / 2 / 3 / 3 / 4 / 6 / 8 / 8
4 / 0 / 1 / 3 / 6 / 7 / 8 / 9 / 9

Key: 1 | 1 means 11

Feedback
A / Write the ones digit each time a number is repeated.
B / Correct!
C / The tens digit is in the "stems" column, and only the ones digit is in the "leaves".
D / The tens digit is in the "stems" column, and only the ones digit is in the "leaves". Write the ones digit each time a number is repeated.

2.ANS:B

The least stem and least leaf give the least value: 22.

The greatest stem and greatest leaf give the greatest value: 52.

Use the data values to find the mean: .

The median is the average of the middle values: 33.

The mode is the number that occurs most often: 28.

The range is the difference between the greatest and least value: 30.

Feedback
A / The median is the average of the middle values.
B / Correct!
C / The mode is the number that occurs most often.
D / A data value consists of a stem and a leaf.

3.ANS:

The least stem and least leaf give the least value, 63.

The greatest stem and greatest leaf give the greatest value, 93.

To find the mean, you must add up all the values and divide by the number of values in the plot. (63+66+72 ...+93)÷14=84.21

The median is the average of the two middle values in the table, 88.5.

To find the mode, look for the number that occurs most often in a row of leaves. Then identify its stem. The mode is 93.

The range is the difference between the greatest and least value, 93 – 63 = 30

4.ANS:

ACT Scores
Stem / Leaves
1 / 9
2 / 3 4 6 8
3 / 1 2
Key: 1|9 means 19

Place the numbers in order from least to greatest. Group the numbers by their tens digit. The stem column should contain the tens digit of each group in ascending order. Each row of leaves should contain the units digit of each number in that group in ascending order.

Scoring Rubric:
4 / The solution is correct, and the explanation is complete.
or
A different logical method is used to find the correct solution.
3 / The solution is correct, but the explanation is not complete.
2 / The solution is incorrect, but the work shows understanding of the concept.
1 / The solution is incorrect, and the work shows no understanding of the concept.

5.ANS:

Hundreds of Acres Lost in Forest Fires
Stem / Leaves
1 / 2 5 7 9
2 / 0 3 7
3
4 / 5 8
5 / 7
6 / 0 5
7 / 0
8
9
10 / 1
Key: 1|5 means 15

6.ANS:A

Step 1 Choose equal intervals.

Step 2 Find the number of data values in each interval. Write these numbers in the “Frequency” row.

Feedback
A / Correct!
B / The sum of numbers in the table must be 20.
C / Three students received a score of 90 or greater.
D / The sum of numbers in the table must be 20.

7.ANS:A

Create a histogram, labeling the x-axis with the elements in “Numbers”. Use the elements in “Frequency” to create the height of each box in the histogram.

Feedback
A / Correct!
B / Make sure the labels for each axis are correct.
C / The frequency chart emphasizes different ranges. This needs to appear on the graph.
D / Make sure the labels for each axis are correct.

SHORT ANSWER

8.ANS:

Number / 1–5 / 6–10 / 11–15 / 16–20
Frequency / 2 / 6 / 2 / 5

9.ANS:

10.ANS: