0
When adding or subtracting fractions do you have to have the numerator the same or denominator?
Wiki User
∙ 15y ago
The denominators must be the same, the numerators can be different.
Wiki User
∙ 15y ago
Add your answer:
Earn +20 pts
How is multiplying fractions by a whole number is different from adding adding and subtracting fractions with like denominators?
Adding and subtracting fractions can ONLY be done if the denominators are the same; then the calculation is done by adding or subtracting the numerators. Multiplying (and dividing) fractions does not require the denominators to be the same. To divide by a fraction the divisor is inverted (the original numerator becomes the new denominator and the original denominator becomes the new numerator) and then the fractions are multiplied. Multiplying fractions is achieved by multiplying the numerators together AND multiplying the denominators together. A whole number is the same as a fraction with the whole number as the numerator and a denominator of 1, so when multiplying by a whole number the denominator is multiplied by 1 (leaving it the same) and the is multiplication is effectively just multiplying the numerator by the whole number.
Why do you find LCM and HCF?
When simplifying fractions it's useful to know what is the HCF of the numerator and denominator is. When adding or subtracting fractions with different denominators it's useful to know what the LCM of them is.
Adding and subtracting unlike fractions steps?
first u find a common denominator
How do you check you math with adding fractions?
When adding or subtracting fractions first make sure that the denominators are the same if they aren't then find the lowest common denominator and alter the fractions accordingly
What is the definition of adding and subtracting fractions with unlike denominators?
What is the definition of Adding and Subtracting Like Fractions
When adding or subtracting fractions do you change the numerator?
you subtract the numerator but the denominator stays the same.
Does the numerator or denominator change when adding or subtracting?
numerator
How is multiplying fractions by a whole number is different from adding adding and subtracting fractions with like denominators?
Adding and subtracting fractions can ONLY be done if the denominators are the same; then the calculation is done by adding or subtracting the numerators. Multiplying (and dividing) fractions does not require the denominators to be the same. To divide by a fraction the divisor is inverted (the original numerator becomes the new denominator and the original denominator becomes the new numerator) and then the fractions are multiplied. Multiplying fractions is achieved by multiplying the numerators together AND multiplying the denominators together. A whole number is the same as a fraction with the whole number as the numerator and a denominator of 1, so when multiplying by a whole number the denominator is multiplied by 1 (leaving it the same) and the is multiplication is effectively just multiplying the numerator by the whole number.
When adding or subtracting fractions you must get a?
A Common Denominator
How is subtracting fractions like adding fractions?
You need a common denominator for both.
Before adding or subtracting Why are fractions turned into like fractions?
They have to have the same denominator.
Do you need a common denominator for dividing fractions?
No only when adding or subtracting fractions a common denominator is needed
Why do you find LCM and HCF?
When simplifying fractions it's useful to know what is the HCF of the numerator and denominator is. When adding or subtracting fractions with different denominators it's useful to know what the LCM of them is.
What is always needed when adding and subtracting fractions?
a common denominator
Why do you have to have a common denominator?
A common denominator is needed when adding or subtracting fractions of different denominators.
When adding or subtracting two fractions what is a necessary requirement?
A common denominator.
What two operations reequire a common denominator?
Adding and subtracting fractions.
