Big Book about Fractions

By Mrs. Bader

The important thing about fractions is that they are parts of a whole.

Fractions are small parts of something. Each part is called a unit fraction.

When your object or shape is complete it is whole or one unit.

Fractions are written with two numbers that each have a meaning.

The bottom number is called the denominator. It tells you how many equal parts the whole has been divided into.

The top number is called the numerator. It tells you how many of the equal parts are used in this fraction.

If the numerator and denominator are the same, the fraction equals one whole.

The numerator and denominator are divided by a line called a vinculum.

4 4 = 1

3 Vinculum4

But the important thing about fractions is that they are parts of a whole.

If the denominators of two fractions are different, that tells you that the whole has been divided into different equal parts. Larger denominators mean the whole has been divided into more parts, so the unit fraction is smaller.

If the fractions have the same denominator, the larger the numerator the bigger the fraction.

2/3 is greater than 2/5 Thirds are bigger than fifths

4/6 is greater than 2/6

The important thing about fractions is that they are parts of a whole. An improper fraction has

a numerator the same or larger than the denominator.

Some people call it a “top heavy fraction.”

Improper fractions are not improper, or incorrect. They are an acceptable and sometimes preferable form of fraction.

3/3 = 1 5/3

A mixed number is a whole and a fraction.

Mixed numbers are understood to be addition expressions, but when they are written the addition symbol is not written.

Improper fractions can be turned into mixed numbers. They are equivalent.

2 + ½ = 2 ½

But the important thing about fractions is that they are parts of a whole.

To convert a mixed number into an improper fraction multiply the whole number by the denominator, then add the numerator.

To convert an improper fraction into a mixed number, divide the numerator by the denominator. The remainder is the new numerator.

The important thing about fractions is that they are parts of a whole.

Fractions can be added or subtracted.

To add or subtract fractions with like denominators, just add or subtract the numerator.

If the fraction is a mixed number, add the wholes, then the numerators. The denominator stays the same.

If the sum is an improper fraction, it needs to be converted into a new mixed number.

2 - 1 = 1 6 6 6

You can also add and subtract fractions with unlike denominators, but first you need to rewrite the fraction so the denominators are the same.

We call this finding the least common denominator.

A common denominator is a number that is a multiple of both denominators.

1 + 1 = ? 3 4Find the least common denominator

Step 1 1 4 = 4 3 4 12Step 2 1 3 = 3 4 3 12Step 3 4 + 3 = 7 12 12 12

Fractions can be the same, or equivalent, if they represent the same part of a whole.

Simplifying a fraction means finding an equivalent fraction with a smaller numerator and denominator.

To simplify a fraction, find the largest number that both the numerator and denominator can be divided by.

10 2 = 5 12 2 6

6 6 = 1 18 6 3

But the important thing about fractions is that they are parts of a whole.

Knowing how to work with fractions can help you in your everyday life. If you want to bake

more cookies, how do you expand your measurements?

What is 5/8 inches plus 1¾ feet? Will all my boards be cut the same length?

Would you like 1/3 more or 1/4 more recess?

How can we divide up this pizza equally?

The important thing about fractions is that they are parts of a whole.