Name
16.4
?
5.9.C
Analyze Stem-and-Leaf Plots
Essential Question
Data Analysis—
MATHEMATICAL PROCESSES
5.1.A, 5.1.D, 5.1.F
How can you analyze data displayed on a
stem-and-leaf plot?
Unlock
Unlock the
the Problem
Problem
A stem-and-leaf plot is useful when you need to see every item in a data
set to solve a problem.
Example 1
The stem-and-leaf plot shows the points scored by hockey players this season.
The average number of points scored last season was 35. How many players’
scores are greater than last year’s average? What are the scores?
Points Scored by Hockey Players
Stem
Leaves
2
3
4
6
0
3
8
1 2 4
7 9 9
5
0
1
5 6 6
9
7
2|6 represents 26.
• Locate 35 on the stem-and-leaf plot.
stem: _ leaf: _
• Count the numbers greater than 35.
There are _ numbers greater than 35.
So, _ players’ scores are greater than last year’s average.
The scores are ______.
Math Talk
Mathematical Processes
Describe another conclusion
you can draw about the data
in the stem-and-leaf plot.
© Houghton Mifflin Harcourt Publishing Company
• How many points did the greatest number of players
score? Explain.
Module 16
589
Example 2 Solve a multi-step problem.
The stem-and-leaf plot shows the amounts of money the first
32 customers spent at the opening of an electronics store. Customers
who spent $50 or more received a $12 coupon. Customers who spent
less than $50 received a $7 coupon. What is the total value of the
coupons the customers received?
STEP 1 Find the number of customers who spent $50 or more.
Multiply the number by $12.
Money Spent by Customers ($)
Stem
_ × $12 = $_
STEP 2 Find the number of customers who spent less than $50.
Multiply the number by $7.
_ × $7 = $_
Leaves
3
4
5
3
1
0
4 6 7 9
2 3 4 5
5 5 6
6
2
6 6 8
7
0
2
3
4
8
4
6
7
7 7 9
3|3 represents 33.
6
7
8
5
STEP 3 Add to find the total value of the coupons.
$_ + $_ = $_
So, the total value of the coupons is $_.
Share
Share and
and Show
Show
Students made a stem-and-leaf plot to show daily high temperatures.
Use the stem-and-leaf plot for 1–3.
1. What is the range of temperatures?
Leaves
least temperature: _°F
6
7
8
4
4
0
8 8
5
0 7
7
7
8 8 9
_–_=_
9
1
2
3
4
5
The range is _ °F.
2. On how many more days was the high
temperature in the 80s than the 90s?
590
Stem
3
9
9
8
6|4 represents 64.
3. What were the temperatures on the days when
it was less than 80°F?
© Houghton Mifflin Harcourt Publishing Company
greatest temperature: _°F
Daily High Temperatures (˚F)
Name
Problem
Problem Solving
Solving
4.
5.
What’s the Error? Jenny made this
stem-and-leaf plot. She says that on the days when she did
homework for less than 50 minutes, she spent a total of 5 hours
doing homework. What’s the error?
Daily Homework Time (min)
Stem
Leaves
3
4
5
1
0
5
2
3
6
3
3
7
5
7
7
6
6
0
0 2
7
4
6 6 7
3|1 represents 31.
9 9
Multi-Step Pablo started to make a stem-and-leaf plot.
He wrote the stems for the data: 1, 2, 3, 4, 5, and 6. He also wrote this
key: 2|4 = 24. What is the least possible range of the data? What is the
greatest possible range? Explain.
Problem
Problem Solving
Solving
The stem-and-leaf plot shows the number of text messages
Chester received each day for 24 days. Use the stem-and-leaf
plot for 6–7.
6.
Multi-Step On the days that
Chester received more than 50 text messages,,
he responded to only 1_3 of the messages. How
many text messages did Chester respond to?
Text Messages
Stem
Leaves
2
3
4
4
0
0
5 7
2 5
0 3
5
0
1
6
2
2
4
5
4
6 6 6
9
7
8 8
4
© Houghton Mifflin Harcourt Publishing Company
2|4 represents 24.
7.
Write Math
Explain how you can use the stem-and-leaf plot
to make a reasonable prediction about the number of text messages
Chester will receive each day next week.
Module 16 • Lesson 4 591
Mathematical Processes
M
Model ¥ Reason ¥ Communicate
M
Daily
Daily Assessment
Assessment Task
Task
Fill in the bubble completely to show your answer.
Use the stem-and-leaf plot for 8–10.
8. Tom asked people in a survey how much money they
Amounts of Money Found (¢)
could find under their sofa cushions. The stem-and-leaf
plot shows the amounts of money. What is the least
amount of money a person said they could find?
A
4¢
C
46¢
B
45¢
D
456¢
Stem
4
5
6
5
2
3
6
2 7 8
4 9
7
0
0
8
3
9. Which statement about the data is true?
A
Two people each found 70¢.
B
Two people each found 7¢.
C
One person found 56¢.
D
Eight people found 37¢.
Leaves
1
7
5|2 represents 52.
10. Multi-Step Suppose Tom gives two concert tickets to everyone
who participates in the sofa cushion survey. How many tickets
does he give away?
A
10 tickets
B
14 tickets
C
28 tickets
D
38 tickets
TEXAS Test Prep
592
A
4
B
10
C
9
D
11
Distance to Work (mi)
Stem
Leaves
2
3
4
1
0
7
2 3 7 8 9
1 4
8 8 9
5
3
3 3 4 7 9
2|4 represents 24.
© Houghton Mifflin Harcourt Publishing Company
11. How many people live less than 40 miles from work?
H o mewo rk
and Practice
16.4
Data Analysis—5.9.C
MATHEMATICAL PROCESSES 5.1.A, 5.1.D,
5.1.F
Name
Analyze Stem-and-Leaf Plots
Students made a stem-and-leaf plot to show daily low temperatures.
Use the stem-and-leaf plot for 1–3.
1. What is the range of temperatures? Write an
equation to show how you found your answer.
2. On how many days was the low temperature
in the 20s or the 30s?
Daily Low Temperatures (°F)
Stem
2
8 9
3
0 0
4
2 4
5
1 3
Leaves
1
5
5
2
6
6
6
6
7 9
2 | 8 represents 28.
3. What were the temperatures on the days when
the low temperature was greater than 45°F?
Problem
Problem Solving
Solving
Alexandra posted a video on the Internet of her dog performing
a trick. The stem-and-leaf plot shows the number of times
Alexandra’s video was viewed each minute during a 20-minute period.
Use the stem-and-leaf plot for 4–5.
4. The average number of views per minute for a video on
a pet owner’s website is 60. How many times was the
number of views of Alexandra’s video less than
the average?
© Houghton Mifflin Harcourt Publishing Company
5. Alexandra collects data for the next 5 minutes and finds
that the number of views each minute are 88, 86, 95, 87,
and 99. Explain how you can use the stem-and-leaf plot
to make a reasonable prediction about the popularity
of her video.
Number of Video Views
Each Minute
Stem
4
5
6
7
8
Leaves
0 2
1 1 2
0 0 8
2 3 4 4 5 9
2 2 3 4 4 5
4 | 0 represents 40.
Module 16 • Lesson 4 593
TEXAS Test Prep
Lesson
Lesson Check
Check
Fill in the bubble completely to show your answer.
A
9
B
3
C
7
D
5
Points Scored in
Carnival Game
Stem
Leaves
0
6 7 7
1
0 1 1 2
2
2 4
3
0 2 2
0 | 6 represents 6
The stem-and-leaf plot shows the number
of carnival tickets sold each day.
Use the stem-and-leaf plot for 8–11.
8. Ticket sales for the next two days are 55
tickets and 68 tickets. Which statement about
the data is true?
A
The range stays the same.
B
The range increases by two.
C
The range decreases.
D
The range doubles.
10. Multi-Step On any day that the number
of tickets sold is greater than 70, twice that
number of tickets is donated to a children’s
hospital. How many tickets are donated to
the hospital?
594
7. Multi-Step Half the number of guesses are
less than what number?
A
83
B
73
C
74
D
79
Guesses for Number of
Marbles in a Jar
Stem
Leaves
6
5 5 6 8 9 9
7
2 3 3 8 8 9
8
3 5
9
1 2 3 6
6 | 5 represents 65
Carnival Tickets Sold Per Day
Stem
Leaves
4 7 7
3
0 1 2 3 4 4
4
2 2 5 6 7 8 9
5
5 6 9
6
0 1 2 3 3
7
3 | 4 represents 34
9. How many days were carnival tickets sold?
A
24 days
B
29 days
C
20 days
D
39 days
11. How many days are the number of tickets sold
greater than 40 but less than 55?
A
5 days
B
7 days
A
289
C
432
C
6 days
B
718
D
578
D
9 days
© Houghton Mifflin Harcourt Publishing Company
6. How many scores are greater than 20?