http://www.teachersdomain.org/resource/vtl07.math.number.nums.measuredeb/

Using Your Ruler

Using Your RulerMeasure the following objects in your bags with your group members. • Length of the blue calculator (in inches) ____________• Diameter of the fraction circle (in inches) ____________• Length of the screw (in centimeters) ____________• Width of the cube (in centimeters) ____________• Length of the pencil (in inches) ____________• Length of the marker (in inches) ____________• Diameter of the nickel (in centimeters) ____________• Length of the toothpick (in centimeters) ____________• Length of the clear plastic tab (cm) ____________• Width of the clear plastic tab (cm) ____________

1. Length of the blue calculator (in inches) ____________2. Diameter of the fraction circle (in inches) ____________3. Length of the screw (in centimeters) ____________4. Width of the cube (in centimeters) ____________5. Length of the pencil (in inches) ____________6. Length of the marker (in inches) ____________7. Diameter of the nickel (in centimeters) ____________8. Length of the toothpick (in centimeters) ____________9. Length of the clear plastic tab (cm) ____________10.Width of the clear plastic tab (cm) ____________

Using Your Ruler

Real Numbers and Number LinesReal Numbers and Number Lines

The number that corresponds to a point on a number line is called the_________ of the point.coordinate

On the number line below, __ is the coordinate of point A.

The coordinate of point B is __

Point C has coordinate 0 and is called the _____.

-4

10

origin

x

11-5 -3 -1 1 3 5 7 9-6 -4 0 4 8-6 2 106-2

AB C

x

11-5 -3 -1 1 3 5 7 9-6 -4 0 4 8-6 2 106-2

Look at the coordinate points below. What is the distance of segment DE?

What is the distance of segment EF?

What is the distance of segment DF?

D E F

You can also use number lines to find the distance between points, just like a ruler.

Real Numbers and Number LinesReal Numbers and Number Lines

The distance between two points A and B on a number line is found byusing the Distance Postulate.

Postulate:DistancePostulate

Points on a line are paired with real numbers, and the measure ofthe distance between two points is the positive difference of the corresponding numbers.

measure = a – b

B A

ab

Real Numbers and Number LinesReal Numbers and Number Lines

x

11-5 -3 -1 1 3 5 7 9-6 -4 0 4 82 106-2

AB

10 2AB

8

8

2 10BA

8

8

1 2 43 5 76 8 9 10 11

What is the distance of segment XY on the line below?

X Y

220 380

Calculate by subtracting and then taking the absolute value.

220 – 380 = -160

Absolute Value of -160 = 160

M N O

-21 -11 6

Real Numbers and Number LinesReal Numbers and Number Lines

Traveling on I-70, the Manhattan exit is at mile marker 313.The Hays exit is mile marker 154.

What is the distance between these two towns?

313 154

159

159 miles

MH

http://www.michigan.gov/mdot/0,4616,7-151-9622_11033_11151-65571--,00.html