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Course: 5th grade > Unit 4
Lesson 5: Adding and subtracting fractions with unlike denominators word problemsAdd and subtract fractions: FAQ
Frequently asked questions about adding and subtracting fractions.
How do we estimate fractions to add or subtract them?
One way to estimate fractions is to round them to the nearest half or whole number. For example, rounds to , and rounds to .
Try it yourself with this exercise:
How do you add and subtraction fractions visually?
To add or subtract fractions, they need to have the same denominator. We can use fraction bars to visually compare the fractions so we can add and subtract.
Try it yourself with this exercise:
What's the difference between adding and subtracting fractions with like denominators and adding and subtracting fractions with unlike denominators?
When the denominators are the same, we can add or subtract the numerators directly. When the denominators are different, we need to find a common denominator first.
Try it yourself with these exercises:
How do we find common denominators?
There are a few different ways to find common denominators. One way is to use the least common multiple (LCM) of the two denominators. Another way is to just multiply the two denominators together.
Try it yourself with these exercises:
What are mixed numbers and how do we add and subtract them?
Mixed numbers are numbers that contain both a whole number and a fraction. For example, is a mixed number.
To add and subtract them, we have to find a common denominator. Then, we rewrite the mixed numbers as improper fractions with that denominator. Lastly, we add or subtract the two improper fractions together and simplify the result if needed.
Try it yourself with these exercises:
Want to join the conversation?
- this is really helpful(21 votes)
- how to regroup mixed numbers and what is regrouping?(10 votes)
- so first for example we have 1 and 1/4 it would be the same as 5/4 please upvote if you found useful(0 votes)
- A+ to you all because I said so(13 votes)
- are you serious now bro(2 votes)
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- Vector OH YEAH(12 votes)
- do you watch minions?(2 votes)
- try to solve this problem
1/4+1/8+9/4+5/1(2 votes)- the answer in fraction is 61/8 or 7 5/8
in decimal it is 7.625(12 votes)
- If I could make a problem then I would say 5 3/100- 5 1/5(8 votes)
- How are you supposed to solve a fraction problem where you are taking away a smaller number from a bigger one. Take this example.
1/2-2/5
You cannot take 2 away from 1 without getting a negative number, but 2/5 is smaller then 1/2, so how do you solve the problem.(4 votes)- First you find the least common denominator of 2 & 5, which is 10. Then you take the number you multiplied by to get to the least common denominator and multiply the numerater by that, which would be 5/10 & 4/10. Then you subtract the numerators. The answer should be 1/10(7 votes)
- it does not help mi(5 votes)
- so you write all the numbers multiples down like 12 in 3 and 4
and that the LCM(1 vote)
- how do you regroup t improper fractions(4 votes)
- For example, if you had 8/3, 3 goes into 8 twice without going over, and then you have 2 left. So your fraction would be 2 and 3/8(4 votes)