The Meaning Of Fractions Lesson
Improper Fractions And Mixed Numbers Lesson
Several ways to illustrate fractions.
Draw on board - Circle and divide into four sections. Shade three sections.
Ask - What fraction of circle is shaded. = �.
Draw on board - Flowers 4 daisies, 3 tulips, and 2 of pansies.
Ask - What fraction of the flowers are daisies. = 4/9.
Draw 4/5 on a numberline.
Ask the parts of a fraction.
The Numerator of a fraction tells how many parts are being considered. It is the top part of a fraction.
The Denominator of a fraction tells how many parts there are in all. It is the bottom part of a fraction.
E.g. 5/8 =
5 = numerator and parts considered.
8 = denominator and parts in all.
Exploring Fractions
Review: What is a numerator? Denominator?
Get out a chessboard.
Inquire :
1. How many of the squares are dark brown?
2. What is the total number of squares?
3. How many dark brown playing pieces are there?
4. What fraction of the pieces are dark brown?
Another example:
You collect old coins.
You have seven coins dated 1929.
Five of them are dimes.
What fraction of the coins are dimes?
Equivalent Fractions
Ask: Six students have their picture taken. Three of them wear blue shirts.
What fraction of the students wore blue shirts.
3/6
3/6 = �
The fractions 3/6 and � are part of the same group.
They are called equivalent fractions because they have the same value.
To write equivalent fractions you multiply the numerator and the denominator by the same number.
Multiplying:
E.g. � =
1 x 2
4 x 2
= 1/8
Draw grid of 8 (2x4) squares and shade two.
Dividing:
E.g. 9/12 =
9 divided by 3
12 divided by 3
= 3/4
Draw grid with 12 (3x4) squares and shade nine.
A fraction is in simplest form or lowest terms when the numerator and the denominator have no common factors other than 1.
What are factors?
Factor: Any one of the numbers used in multiplication to form a product.
E.g. Express 6/8 in its lowest form.
Draw a pie with six slices and two are gone.
Ask: What are the factors of six.
1,2,3, and 6.
Ask: What are the factors of eight.
1,2,4, and 8.
Ask what the greatest common factor is.
2.
Divide the numerator and the denominator by 2.
So, the simplest form of 6/8 is �.
Improper Fractions and Mixed Numbers
Improper Fraction:
The numerator is larger than the denominator. It represents more than the whole.
Draw:
= 12/5
= 5/3
Changing a mixed number into an improper fraction:
12/5 = 2 2/5
5/3= 1 2/3
Write the whole number and the remainder over the divisor.
Write 2 3/4 as an improper fraction.
Multiply the whole number by the denominator.
Add the numerator to the product.
Write the sum over the denominator.
So 2 3/4 = 11/4
One half of the students wore blue shirts.
Division