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Why do you need a common denominator to add and subtract fractions?
Wiki User
∙ 11y ago
To get the correct answer. If you were adding 1/5 and 1/7, you might not know that the answer is 12/35 unless you knew that 1/5 = 7/35 and 1/7 = 5/35
Wiki User
∙ 11y ago
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What are fraction that have same denominator called?
They are called like fractions.In order to add or subtract fractions you will usually need to convert them to like fractions. Then you simply add or subtract the numerators (as required) to form the numerator of the answer. The same (or common) denominator is the denominator of the answer. You may need to simplify the resulting fraction.
What are compatible numbers for fractions?
I am not entirely sure what you mean, but if you need to add, subtract, or compare two fractions, they need to have the same denominator.
What is the least common denominator of 9?
You need at least two numbers to find a common denominator.
How do you find LCD in complex numbers?
I don't know if this will result in a least common denominator or not, but here is a system that you can use. Suppose you have the complex fraction: (a + bi)/(c + di) where {a,b,c & d} are all real numbers, and i is the imaginary unit number. What I would do is get the denominator to a real number, then use this same procedure for other fractions that you want to add or subtract, then find the LCD between those fractions will real-number denominators.So the first step is to get the fraction to have a real-number denominator. Do this by multiplying the numerator and denominator by the complex conjugate of the denominator. The conjugate of (c + di) is (c - di), so (c + di)*(c - di) = c² - cdi + cdi + d² = c² + d², and (a + bi)*(c + di) = ac + adi + bci - bd = (ac - bd) + (ad + bc)i,so the new equivalent fraction equals:(ac - bd) + (ad + bc)i----------------------c² + d²Now do the same for the other fractions. You will have fractions in which all denominators are real numbers, then you can find LCD between these new equivalent fractions.
The common denominator 32?
You need at least two denominators to find something in common between them. If that's 3 and 2, the common denominator is 6..
What you need to add or subtract fractions?
You need a common denominator in order to add or subtract fractions.
Do you need a common denominator for all fractions before doing the order of operations?
You DO need a common denominator to add, subtract, or compare fractions. You DO NOT need a common denominator to multiply or divide fractions.
How do you subtract fractions in simplest form?
You first need to find a common denominator, not necessarily the least common denominator. Next, you rename the fractions according to the common denominator. Only then can you subtract the fractions. After subtraction you should simplify the answer.
How do you subtract two fractions?
You have to find a common denominator, multiply them, subtract them and then simplify if you need to.
Why do you need a common denominator?
Common Denominator means that the denominators in two (or more) fractions are common, or the same. The common denominator is important because before you can add or subtract fractions, the fractions need to have a common denominator.Sometimes fractions have different denominators, like 2/3 and 3/4. If you want to add or subtract them, they need to have the same denominator. In order to do that, you find a common denominator which is the same thing as a common multiple, only with denominators.
Why do you need a common denominator with fractions?
You can add or subtract fractions only if they are "like" fractions, that is, only if they have the same denominator - unless you know your fractions really well.
Why do you need to use common denominator?
To get the right answer when you add or subtract unlike fractions.
When do you need a common denominator?
The denominators must be the same before you can add or subtract fractions.
Why do fractions need a common denominator before you add or subtract?
Because the answers will be wrong when adding or subtracting them if they don't have a common denominator.
How is finding the LCM revelant when adding and subtracting fractions?
To add and subtract fractions, you need common denominators. To find the common denominator, find the LCM of the denominators you wish to add or subtract.
Why do fractions need to have a common denominator before add or subtract them?
because it would be diffcult to understand.[you don't add or subtract the demonters]
How do you subtract Fractions with models unlike denominators?
The denominators need to be the same for subtraction. Find the Least Common Denominator for both items and then subtract.
