Transcript SCO A2: Students will be expected to interpret and model decimal

SCO A10: Students will be expected to
compare and order fractions using
conceptual methods.
Introductory Activity 1:
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There are several different strategies for
comparing fractions to see which is larger
and which is smaller.
One of the strategies is to compare the
fractions that are given to what is called ‘a
benchmark’. This is a common fraction
such as ½.
Use this ‘benchmark’ strategy to compare
1/8 to 3/5. Which is greater?
Compare ¼ to 2/3. Which is smaller?
Introductory Activity 2:
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Another one of the strategies for comparing
fractions is to look to see if they have the
same denominators such as in the fractions
11/12 and 9/12 where the denominator is
12 and the numerators are 11 and 9. So we
have 11-twelfths compared to 9-twelfths. It
is easy to see which is larger.
The answer is 9-twelfths.
Compare 8/9 with 6/9.
Compare 12/23 to 21/23.
Introductory Activity 3:
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Another one of the strategies for comparing
fractions is to look to see if they have the same
numerators yet two different denominators.
Which is greater: 10/7 or 10/6? Draw a picture
to show each of these. Remember you are
comparing the same number of sevenths with the
same number of sixths. What would you rather
have, a piece of pizza divided into 6 parts or a
piece of the same pizza divided into 7 equal
parts?
Introductory Activity 4 Practice:
Which is greater: 3/10 or 3/8?
 Yes, I know that 3/8 > 3/10 because eighths
are larger than tenths.
 Which is greater: 3/8 or 7/10?
 Yes, I know that 7/10 is greater than 3/8
because 3/8 is less than ½ while 7/10 is
greater than ½ (5/10).
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Introductory Activity 5:
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What kind of fraction is 7/8?
What kind of fraction is 10/8?
How can the improper fraction 10/8 be written as
a mixed number?
We can use our knowledge about improper
fractions and mixed numbers to compare
fractions? For example, which is greater: 10/8 or
7/5?
I know that 7/5 is 1 and 2/5 while 10/8 is 1 and
2/8, and because 2/5 is greater than 2/8, 7/5 is
greater than 10/8.
Introductory Activity 6:
Sometimes, fractions can be compared by
renaming fractions.
 For example, we can compare 3/5 to 7/10
by renaming 3/5 as 6/10. Because 6/10 is
less than 7/10, 3/5 must be less than 7/10.
 Which is greater: ¾ or 5/8?
 Which is smaller: 2/8 or ¾?
 Which is greater:
10/7 or 5/3? (Clue:
rename 5/3 as 10/6).
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Student Activity A10.1:
Use the pattern blocks provided to you and
arrange them to model (show) two different
fractions where one of the fractions is less than
the other. Record the number sentence that
describes the model.
 For example, 1/3 > 1/6.
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Student Activity A10.2:
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Select or choose, from the digits 1 to 9, so
those digits that can fill the boxes to make true
statements. Give three different possibilities.
>
Student Activity A10.3:
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Explain how you know that 1/3 < ¾?
Student Activity A10.4:
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If you know that 2 / * > 2 /7, what do you
know about the value of * ? Explain.
Student Activity A10.5:
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Order the fractions below from least to
greatest. Be prepared to explain your choices.
2/5
1/4
6/5
7/8
5/10
Student Activity A10.6:
Work with a partner to conduct an experiment.
Roll a pair of coloured dice. The number on the
red die is to be used as the numerator of a
fraction while the number on the blue die is to
be used as the denominator.
 Before you begin rolling, predict whether or
not the fraction will usually be less than ½.
Carry out several rolls of the dice to check out
(verify) your predictions.
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Student Activity A10.7:
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Work in pairs to find different ways to show
which is greater: 7/8 or 5/6. Be prepared to
explain you thinking.
http://www.spacesciencegroup.nsula.edu/lessons/
defaultie.asp?Theme=math&PageName=fractions