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When multiplying fractions, the fractions do not have to have the same denominator as when adding or subtracting. You just multiply the numerators and multiply the denominators, then reduce if necessary.
Example : 3/4 x 5/7 -- multiply 3 times 5 and 4 times 7 = 15/28
Example : 2/3 x 6/7 -- multiply 2 times 6 and 3 times 7 = 12/21
* In this case, you can divide by 3/3 to reduce the fraction to 4/7
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Who invented adding and subtracting fractions?
Me
Why do you have to have a common denominator?
A common denominator is needed when adding or subtracting fractions of different denominators.
Adding and subtracting fractions?
Pulled and mulled
What is a real world situation where it is useful to know about factors and multiples?
When adding or subtracting fractions with different denominators and when reducing fractions to their lowest terms.
What is an LCD in math?
LCD means lowest common denominator which is needed when adding or subtracting fractions that have different denominators.
What are the rules for adding subtracting multiplying and dividing fractions?
no answer
How do you find a multiple when subtracting fractions?
Same as adding, multiplying, and dividing.
Can you multiply fractions that have a different demonminator?
Yes. When multiplying and dividing fractions your denominators do not have to be the same. The denominators only haveto be the same if you are subtracting or adding them.
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.
How are adding fractions different?
When adding or subtracting fractions their denominators must be the same
How do you solve all fractions problems?
You basically have to learn separately how to do different things with fractions, including finding a common denominator; converting fractions to a different denominator; simplifying fractions; adding and subtracting fractions; multiplying fractions; dividing fractions.
How are adding subtracting decimals different from multiplying them?
They aren't. The rules are the same as those for adding/subtracting or multiplying integers. Just be careful of the decimal point's location.
What is the definition of adding and subtracting fractions with unlike denominators?
What is the definition of Adding and Subtracting Like Fractions
How do you subtract improper fractions with different denominators?
It's the same thing as adding or subtracting normal fractions - just make sure both fractions have the same denominators (by either multiplying the denominators or simplifying the fraction - whichever the question needs).
How are adding and subtracting fractions similar?
Subtracting a fraction is the same as adding its negative.
What types of problems can be solved using the the LCM?
Anything having to do with adding or subtracting unlike fractions.
What are the rules for adding fractions?
Ensure that the denominators are the same when adding or subtracting fractions.
