1 mile
P Parking lot Henson Creek Trail Local Road Major Transportation Route Palm
erRd.
SaintBarnabasRd.
Oxon HillRd. Indian
Head Hwy.
Liv ingston
Rd.
Tucke r Rd.
Tucker Rd.
Bock Rd.
Bock Rd.
Bri nkleyRd.
Allento
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Temple H ill Rd.
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8. a. Explain why 0.3 is placed correctly on this number line.
b. On Student Activity Sheet 8, fill in each of the empty circles with an appropriate decimal number.
c. Place the following decimal numbers on this number line: 0.7, 2.1, and 3.4.
miles
0 1 2
0.3
The signpost from problem 6 shows the distance to Tucker Road and the distance to Bock Road.
9. What is the distance from Tucker Road to Bock Road?
0.1 mile
Notes
8 and 9Watch students as they work on these problems to see how well they understand decimals.
If students are having difficulty, discuss this problem with the whole class.
29 Models You Can Count On
Reaching All Learners
Intervention
If students struggle with problem 9, point them to the number line in problem 8. This will also help them with the problems on the next page.
Extension
Walking Trails, Passing Tom’s House, and East of Yaksee Cave from pages 40–43 of Numbers Tools, are all good activities to use during this section.
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Hints and Comments
Materials
Student Activity Sheet 8 (one per student)
Overview
Students review decimal numbers with one decimal place. They write decimal numbers to given points on a number line, and they locate given decimal
numbers on a number line. They also find the distance between two roads indicated on a signpost.
About the Mathematics
A fraction bar gives visual support for the decimal notation of tenths. Students will have more practice locating decimal numbers on a number line on the following page.
When students find the distance between the two roads, they informally subtract two decimal numbers.
Students will practice this more on pages 31–33 with the Jump Jump Game.
Solutions and Samples
8. a. Explanations will vary. Sample explanation:
Because 0.3 is three steps of one-tenth of a mile along the number line.
b.
c.
9. 2.8 2.1 0.7 mi
Section C: The Number Line 29T
miles
0 1 2
0.3 0.9 1.4 2.5 3.1
miles
0 1 2
0.7 2.1 3.4
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The
Number Line C
Sam and Nicole continue their bike trip along the trail. After a while, they see this signpost.
10. How do you know that this signpost is where Brinkley Road crosses the trail?
Indicate the location of this signpost on the map of Student Activity Sheet 8.
The Number Line
C
The bike trail crosses Bock Road, Tucker Road, and Oxon Hill Road. To get a better picture of all of the distances, you can use a number line representing the trail. The signpost from problem 10 is placed at zero (0) location.
Use Student Activity Sheet 9 to answer problems 11–13.
11. Locate where the trail crosses each of the following roads: Bock Road, Tucker Road, and Oxon Hill Road. To save space, use arrows to connect each road to its location on the number line.
12. How many miles did Sam and Nicole bike from the first signpost to the signpost at Brinkley Road?
13. On the number line in problem 11, indicate where the bike trail crosses Temple Hill Road.
Notes
12 If students are having difficulty with this
problem, suggest they try to place the first signpost on the number line from problem 11.
12 and 13 Be sure to discuss students’ solutions and strategies for these problems.
13 Some students may need you to suggest that they extend the number line to the left to solve this problem.
30 Models You Can Count On
Reaching All Learners
Intervention
Encourage struggling students to count slowly and carefully when moving on a number line.
Extension
Assign additional distances that students can place on a number line.
These distances can be in either direction.
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Hints and Comments
Materials
Student Activity Sheets 8 and 9 (one per student)
Overview
Students continue working with decimals. They locate a second signpost on the map. Then they use a number line as a model for the trail to locate crossings of the trail and the roads. They use this model to find distances.
Comments About the Solutions
11. Students should be able to locate decimal numbers on a number line by now.
12. There are different strategies to find an answer.
(See Solutions and Samples.)
Solutions and Samples
10. Explanations will vary. Sample explanations:
• You can read on the signpost that it is on Brinkley Road southwest.
• There are no arrows on the side where you can read Brinkley Road, so you are on Brinkley Road.
The location of this signpost is between Bock Road, Tucker Road, and Oxon Hill Road on the one side and Temple Hill Road on the other. It is closer to Temple Hill Road than to the roads in the opposite direction. Therefore, it is at the indicated spot.
11. Bock Road at 1.8; Tucker Road at 2.5;
Oxon Hill Road at 5.1.
12. 4.6 mi.
Several explanations are possible. Sample explanations:
• Reading from the first signpost 2.8 (to Bock Road) 1.8 (Bock Road to Brinkley Road) 4.6
• Reading from the signpost on Brinkley Road 2.5 (to Tucker Road) 2.1 (Tucker Road to first signpost) 4.6
• Reading from the signpost on Brinkley Road 5.1 (to Oxon Hill Road) 0.5 (Oxon Hill Road to first signpost) 4.6 13. 0.6 to the left of zero.
Section C: The Number Line 30T
Bri nkleyRd.
Allent
wo
Rn
d.
Temple H ill Rd.
N
x
Answer to problem 10.
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