Common Denominators
What is a common denominator?
a number that is a multiple of both denominators
Can you add fractions with unlike denominators?
Yes, but you have to convert to common denominators first
What is a mixed number? How is it different from a fraction?
It is a more than one, it is a whole number and a part of another whole number
What on earth is an improper fraction?
It is a fraction greater than one where the numerator is larger than the denominator.
What do you do when finding common denominators?
List the multiples of both denominators and find ones they have in common.
How can you find a common denominator of two unlike denominators?
Find the least common multiple of the two denominators.
When adding fractions, do you add the numerators or the denominators?
Numerators only.
When adding or subtracting mixed numbers, what should be your first step?
Subtract the fractions. If you cannot subtract than you must rename.
What do we have to do to improper fractions or fractions greater than one?
Turn them into mixed numbers
When you multiply a denominator by a least common multiple, what happens to the numerator?
You multiply the numerator by the same number.
What is the lowest common denominator of 4 and 6?
12
When subtracting fractions, what do you subtract?
The numerators.
What parts of a mixed number do you add or subtract when adding or subtracting mixed numbers?
The whole numbers and the numerators
How would you change an improper fraction into a proper fraction?
Divide the numerator by the denominator.
When a numerator is greater than a denominator, what is that called? Must give both names.
An improper fraction or fraction greater than one.
What is a least common multiple?
The smallest number two factors have in common.
What is 3/4 + 2/5?
23/20 or 1 3/20
What is 2 5/6 + 1 5/6?
3 10/6 or 4 4/6 or 4 2/3
How would you rename 10/8?
1 2/8 or 1 1/4
Do improper fractions always have to be turned into mixed numbers?
No, but you should always read the question carefully to be sure you are giving the answer that is required.
What is the least common multiple of 7 and 6?
42
What is 8/6 + 7/6?
15/6 or 2 3/6 or 2 1/2
What is 4 1/6-1 2/3?
2 3/6 or 2 1/2
How would you rename 3 7/4?
19/4
What two properties make adding and subtracting mixed numbers with the same denominators easier?
Commutative and Associative