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Question
Hi how do you add and subtract fractions?
When adding and subtracting fraction, we need to have a common denominator.
For example: 3/4 + 2/5...the least common denominator
is 20, so write 3/4 as 15/20 and 2/5 as 8/20
so, 3/4 + 2/5 = 15/20 + 8/20 = (15+8)/20 = 23/20
OK?
Check these sites for more:
http://www.jamit.com.au/htmlFolder/FRAC1007.html
http://www.active-maths.co.uk/fractions/whiteboard/frac_index.html
http://www.teacherschoice.com.au/Maths_Library/Fractions/adding_and_subtracting_...
http://www.themathpage.com/ARITH/add-fractions-subtract-fractions-1.htm
Abe
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Basic Math
Answers by Expert:
Abe Mantell
Expertise
Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!
Experience
Over 15 years teaching at the college level.
Organizations belong to
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.
Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook
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