Butterfly method of adding and subtracting fractions

Butterfly Fractions - adding and subtracting fractions with different denominators

To add or subtract fractions the butterfly way,

1. Write the fractions side-by-side as usual and draw two wings along the diagonals made by the numerator of one fraction and the denominator of the other fraction and draw an antenna on each wing.

2. As suggested by the wings, that look like a multiplication sign, multiply the numbers in each wing and put the product in the antenna for the wing.

3. Think or say: “This poor butterfly needs a body.” To give it a body, connect the bottom parts of the wings with a body-like loop and multiply the two denominators it connects, putting the product inside the body.

4. Add or subtract the numbers in the antennae in keeping with what is being done to the fractions and put the result over the number in the body.

5. If necessary, reduce or simplify the result.

The butterflies below for 3/4 + 2/5 and 3/4 – 2/5 illustrate the procedure. The only difference in subtracting the fractions versus adding them is in the last step where the numbers in the antennae are subtracted instead of added.

You can also use this method to compare fractions. Do the butterfly for the two fractions you are comparing, e.g. if you look at the example above, and you wanted to compare 3/4 and 2/5, you would do as above and see the 3/4 is 15/20, and 2/5 is 8/20, so 15/20 is the largest fraction because 15 twentieths is larger than 8 twentieths.

Butterfly method of adding and subtracting fractionsButterfly Fractions - adding and subtracting fractions with different denominatorsthat look like a multiplication sign, multiply the numbers in each wing and put the product in the antenna for the wing.compare fractions. Do the butterfly for the two fractions you are comparing, e.g. if you look at the example above, and you wanted to compare 3/4 and 2/5, you would do as above and see the 3/4 is 15/20, and 2/5 is 8/20, so 15/20 is the largest fraction because 15 twentieths is larger than 8 twentieths.- Fraction games, fraction worksheets, etc. http://www.dr-mikes-math-games-for-kids.com/fractions.html
- Fraction lessonshttp://jamit.com.au/welcome.html and accompanying
- Interactive games for fractions, decimals and percentages http://www.woodlands-junior.kent.sch.uk/maths/fractions/
- Very cool games to visualize fractions http://themathgames.com/our-games/fraction-games-online
- More visual fraction games http://www.free-training-tutorial.com/equivalent-fractions-games.html
- Cool Math 4 Kids fraction unit http://www.coolmath4kids.com/fractions/
- Stacks and stacks of fraction games http://classroom.jc-schools.net/basic/math-fract.html
- Fraction games http://www.gamequarium.com/fractions.html
- Fractions, decimals and percentages games http://www.sheppardsoftware.com/math.htm
- Fraction Dominoes game to download, print and play:
fractions-dominoes.pdf

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- 114 KB

- Fraction Wall:
fractionwall.pdf

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- 6 KB

- Percentage, Decimals, Percentage mix
percentage,_decimals,_fractions_mix.doc

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- 44 KB

, empty template: percentage,_decimals,_fractions_mix (empty).doc

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- 40 KB

- Fractions Hunt
Fraction Hunt puzzle modified.doc

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- 33 KB

- Fantastic interactive that should be in every teacher's toolbox: See the great fractions to use on IWB or through data projector http://www.glencoe.com/sites/common_assets/mathematics/ebook_assets/vmf/VMF-Interface.html
- Activities and interactives relating to fractions, fraction walls etc. http://www.bgfl.org/bgfl/custom/resources_ftp/client_ftp/ks2/maths/fractions/index.htm
- Heaps of activities, games, worksheets, Smartie fractions, pizza or chocolate fractions: http://www.primaryresources.co.uk/maths/mathsB6.htm
- Stacks of interactive Fraction games: https://fuse.education.vic.gov.au/pages/Results.aspx?s=fractions&d=discipline%2fmathematics
- Action Fraction Game: http://funschool.kaboose.com/formula-fusion/number-fun/games/game_action_fraction.html
- Interactive Fraction activities http://www.shodor.org/interactivate/activities/
- Fractions PPT for the whole class, a game: Who wants to be a Millionaire...Fractions version
fdp_wwtbam.ppt

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- 1 MB

- Cute fraction vids that will play at school (hopefully!)...

Low skills http://www.totlol.com/watch/vjjv1CVjwso/Fractions-Video/0/Free online fraction games http://jamit.com.au/fraction-games.htm

Fraction games, online fraction calculator and fraction worksheets

http://www.homeschoolmath.net/online/fractions.php

Cool interactive fraction games

http://www.maths-games.org/fraction-games.html

Visual fractions

http://www.visualfractions.com/

Online fraction games

http://www.learn-with-math-games.com/online-fraction-games.html

Medium skills: http://www.totlol.com/watch/igU0CpIQJTA/Why-We-Need-Fractions/0/

High skills: http://www.totlol.com/watch/IYizlhPvMWQ/Scale-Models-And-Ratios/0/