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Why can't you easily add or subtract fractions with different denominators?
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How do you add and subtract fractions that don't have common denominators?
Take for example 1/2 and 1/3. Since those denominators are different, one must change them so they do have "common denominators". Most often, the easiest way of doing this is to simply multiply the two denominators, and perform the same function on the top numbers (the numerators). So 2 times 3 is six, so 6 will now be the denominator of both fractions. As you changed the 2 into a 6 by multiplying by 3, you must multiply the 1 above it by 3. This gives you the final first fraction of 3/6. The three in the second fraction was multiplied by 2 to get 6, so you must multiply it's top number by 2. This gives you a final fraction of 2/6 for the second fraction. Now you are dealing with the fractions 3/6 and 2/6, and you can easily add and subtract them.
Why is it necessary to convert two fractions into like fractions before adding and subtracting them?
Because think of like fractions as the same things.. you can subtract halves from halves for example, but what does it mean to take away a half from a third?By converting them into like fractions, we can add or subtract them easily.
What are fifteen facts or more about fractions?
You're only supposed to ask one question at at time but here we go:- 1 Fractions are parts of whole numbers or integers 2 Fractions less than 1 are common fractions 3 Fractions greater than 1 are improper fractions 4 Fractions have denominators which are underneath their numerators 5 Fractions are separated by a solidus line such as n/d 6 Fractions that are improper can be changed into mixed numbers 7 Fractions can be changed into decimals 8 Fractions can be converted into percentages 9 Fractions are rational numbers 10 Fractions can not be derived from irrational numbers 11 Fractions need a LCD when adding or subtracting them 12 Fractions can be easily multiplied and divided 13 Fractions can be equivalent such as 2/3 = 4/6 14 Fractions can be simplified by finding their HCF 15 Fractions use prime numbers to find the LCM of different denominators 16 Fractions were once used by the ancient Romans to a limited extent
What is the sum of three dividide by fifteen plus tweleve dividide by eighteen is?
3/15 + 12/18 = ??? To add (or subtract) fractions a common denominator needs to be found. This is usually the lowest common multiple of the present denominators but if this cannot be easily calculated use the product of the present denominators. The LCM of 15 & 18 is 90. 3/15 = 3x6/15x6 = 18/90 : 12/18 = 12x5/18x5 = 60/90 Then 18/90 + 60/90 = 18+60/90 = 78/90 which can be simplified to 39/45
What is the lcd of 7 4 and 2?
The LCD, or Lowest Common Denominator, is the smallest multiple of each of the denominators of a set of fractions. So, assuming that 2, 4 and 5 are denominators of fractions (1/2, 1/4 and 1/5, for example), the LCD would be 20, because 20 is the lowest number that 2, 4 and 5 multiply into. So, your new fractions would be 10/20, 5/20 and 4/20. The purpose of finding the LCD is to allow for multiplying fractions together, or simply comparing them easily.
How do you add a fraction without a common denominator?
You have to make a common denominator between them, otherwise you can't. See if they have similar factors, or if you can't find any easily, cross-multiply and multiply the numerator and denominator of one side by the denominator of the other side and do the same thing to the other side with the denominator of the other fraction!
Do you use notation to compare and order fractions?
You can use the same notation and ordering for fractions as you do integers. The difficulty with fractions is that in most cases you need to find eqivalent denominators to see how they rank. Ie. If I said order for smallest to largest 2/3, 1/6, 72/96 and 24/48. It would be difficult without finding some similar base (is 2/3>72/96?). Instead if you conver them into a common base... 8/12, 2/12, 9/12, 6/12. Now you can easily order and/or compare the fractions.
How to explan fractions to a sixth grade student?
Use visual aids that you can draw and/or cut yourself. Use objects the child recognizes such as sliced pizza, cake, pie. Also use squares, rectangles and other figures that are easy to "slice" into several pieces. Each piece will be a fraction that can be easily seen and understood. You can use the pieces to add and subtract the fractions.
How do you subtract two and two thirds from eleven and one half?
You need to do two changes before you can do the actual subtraction. One, since 2/3 is more than 1/2, you have to write 11 1/2 as 10 3/2. That is, you add 2/2 to the fractional part, and, to compensate, you subtract the equivalent (2/2 = 1) from the integer part. Two, you have to convert the fractions to a common denominator. Once you have done these two changes, you can easily subtract. (Subtract the integer part and the fractional part separately.)
How do you change a common multiple into a denominator to make it an equivalent fraction?
To use common multiples to make equivalent fractions, use this example:change 2/3 and 5/9 into equivalent fractions.the common multiple is: 9change both denominators to nine (keep in mind: whatever you do to the denominator you must do to the numerator)you get 2/3 = 3 x 3 = 9 so 2 x 3 = 6so 2/3 = 6/9you can now compare 6/9 and 5/9. you can add and subtract easily.
How to compare fractions?
The usual method is to convert the fractions to equivalent fractions with a common denominator. Then you can simply compare the numerators. You can also convert each of the fractions to a decimal - this can easily be done with a calculator, simply divide the numerator by the denominator.
How does a nurse use decimals?
A strong working understanding of fractions and decimals is essential for nurses. They must be familiar enough with fractions and decimals to quickly and accurately divide, multiply, add and subtract dosages as well as convert fractions to decimals and vice versa. Conceptual understating of fractions and decimals is essential since half doses, extra doses and time-delayed dosages must be calculated correctly. Nurses also need to know how to convert fractions and decimals to percentages in order to explain medication instructions accurately and easily to their patients. Read more about how math is related to nursing at the link I provided below.
