Date: 9/6/96 at 22:30:53 From: Anonymous Subject: Visualization of Subtracting Fractions How do I solve 3/4 - 1/2? I tried drawing a circle and marking off the area, but that didn't work.
Date: 9/13/96 at 13:42:42 From: Doctor Mike Subject: Re: Visualization of Subtracting Fractions Hi, Let me see if I understand your question. I assume that the circle comes into it when you visualize fractions as slices of a pie. Just working with the numbers you can get some benefit by seeing that 1/2 is the same as 2/4 so the original problem can be rewritten as 3/4 - 2/4. With the denominators the same it is an easier problem. By the same reasoning which tells you that 3 apples minus 2 apples is 1 apple, you have 3 fourths minus 2 fourths is 1 fourth, or 3/4 - 2/4 = 1/4 . When it comes to pie, if you start with 3/4 of a pie and remove half a pie (= 2/4) then you have 1/4 left. That is, you have a nice generous piece left for me! Yummmmmmmm. I hope this helps. -Doctor Mike, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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