Transcript Document

Always Click on Scooby to Continue
Scooby and the gang have a mystery to solve and they need
your help! So far, all of the clues seem to involve fractions.
So, before they let you use your detective’s skills, you have to
show them that you’re a fractions expert!
Do you have what it takes to join us
and help solve this mystery? We’ll
lead you through a review of fractions
and you might even learn something
new. Then we’ll ask you some
questions and if you can answer them
all by the end of this class period,
we’ll give you a copy of our notes with
all of the clues we’ve found so far.
Maybe you’ll be able to figure out how
the clues fit together. We’re counting
on you, so let’s get started!
Remember, a fraction is a number that
names a part of a whole or a part of a
group.
Fractions are written as two
numbers with a bar between
them like this . . .
3
4
This fraction is read as
“three fourths.”
The numerator tells the number
of parts shaded or shown
3
The denominator shows the
total number of parts
4
Three fourths of the rectangle is
yellow.
What fraction of this
rectangle is shaded
orange?
3
8
5
8
8
3
8
5
Equivalent fractions show the same, equal
amount.
2/3 , 4/6 , and 6/9 are equivalent
fractions. The shaded areas are
the same size.
You can find some equivalent fractions
by multiplying the numerator and
denominator by the same number.
X2
2
3
equals
X2
4
6
You can find other equivalent fractions
by dividing the numerator and
denominator by a common factor.
÷3
9
12
equals
÷3
3
4
X?
1
4
=
2
8
What number have the numerator and
denominator been multiplied by?
3
2
4
÷?
6
3
=
10
5
What number have the numerator and
denominator been divided by?
3
2
4
To write a fraction in simplest form
you need to use equivalent fractions
and common factors. A fraction is in
simplest form when the only common
factor the numerator and denominator
have is 1.
Remember, a common factor is a number
that is a factor of two or more numbers.
Factors of 12: 1, 2, 3, 4, 6, 12
Factors of 15: 1, 3, 5, 15
So, 1 and 3 are common factors of 12 and 15.
These fractions are in simplest form.
1
3
5
6
7
9
2
5
3
4
The only
common
factor of 3
and 4 is 1.
These fractions are not in simplest form.
6
10
2
8
3
9
4
6
6 and 10 have two
common factors: 1
and 2.
2
4
Which of these fractions is not in
simplest form?
9
10
5
8
10
12
3
7
Which of these fractions is in simplest
form AND equivalent to 10/15 ?
15
10
2
3
6
9
3
4
One way to compare fractions is to use
fraction bars.
The yellow area is larger
than the orange area, so
3/4 is greater than 2/3.
Another way to compare
fractions is to find equivalent
fractions with the same
denominator.
Which is greater?
1
2
or
3
8
We can write 1/2 as an equivalent fraction with the
denominator 8. 4/8 is equal to 1/2. Now we can compare the
two fractions and see that 4/8 is greater than 3/8. That
means that 1/2 is greater than 3/8 too.
Choose the greatest fraction.
3
5
2
4
4
6
4
7
Can you put these fractions in order
from least to greatest?
3
4
1
2
7
8
1
2
3
4
7
8
7
8
1
2
3
4
Like, WOW!
You really are a fractions
expert! There’s just one
more thing left to do
before you can help us
with this mystery . . .
Hey, don’t run away now! You’re
almost finished.
Think about these questions and answer them in your Scooby
Workbook. You’ll find them on the first page.
TRUE
FALSE
1. The numerator in a fraction shows the total number of parts.
2. Fractions that have the same denominator are equivalent
fractions.
3. 2/3 is equal to 6/9.
4. It is possible to find equivalent fractions by dividing the numerator and
denominator by a common factor.
5. A fraction is said to be in simplest form when the only common factor the
numerator and denominator have is 1.
6. The fraction 6/14 is in simplest form.
7. 4 is a common factor of 8 and 24.
8. When comparing fractions, you must use fraction bars or models when the
denominators are different.
9. 2/4 is greater than 4/12.
10. These fractions are in order from least to greatest: 1/2 , 7/12 , 5/6
Click here to end the show