Download Rational Numbers on the Number Line

Lesson Topic: Rational
Numbers on the Number Line
Lesson Objective: I can…
Use a number line that extends in
both directions and use 0 and 1 to
locate integers and rational numbers
on the number line.
Understand that the opposite of a
rational number is similar to the
opposite of an integer.
Vocabulary
Rational Number:
A number that can
be represented as
a fraction
Example 1: Graphing Rational
Numbers
Graph the number 3/10 and its
opposite on a number line.
Example 2: Rational Numbers and
the Real World
The water level of a lake rose 1.25
feet after it rained.
a.
Write a rational number to
represent the situation.
b.
What two integers is 1.25
between on a number line?
c.
What is the length of each
segment on the number line
as a decimal and a fraction?
Example 2: Rational Numbers and
the Real World
The water level of a lake rose 1.25
feet after it rained.
d. What will be the water level
after it rained? Graph the point
on the number line.
e. After two weeks of rain, the
water level of the lake is the
opposite of the water level before
it rained. What will be the new
water level? Graph it.
Example 2: Rational Numbers and
the Real World
The water level of a lake rose 1.25
feet after it rained.
f. What is a rational number that is
not an integer whose value is less
than 1.25? Which two
consecutive integers is it
between?
g. What does zero represent?
h. What do the negative numbers
represent?
Example 3 – On Your Own
Graph -7/4 and its opposite on
a new number line.
 Which two consecutive
integers is the fraction -7/4
located between?
 How did you find its
opposite?
Example 4 – Group Work
Write a real-world story problem using a
rational number and its opposite.
 Create a horizontal or vertical number line to
represent your situation: Be sure to have an
appropriate scale and label your number line,
including the units of measurement if needed.
 Graph the rational number and its opposite.
 What does 0 represent?
 What does the point’s opposite represent?
 Give a rational number to the left and right of
the one you chose.

Lesson Summary…
Look
at the denominator of
a fraction to determine the
scale on the number line
Look at the numerator to
determine where to graph
the point and its opposite in
regard to zero
Evaluate Your Learning
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3
2
1
How will you “Sharpen Your Saw”?