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I am wondering if I can use me standard calculator to solve fraction problems which include: adding, subtracting, multiplying, and dividing fractions, or do I need to buy a scientific calculator to solve them?

Veronica
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    Do you need the results to be exact? That is, if you ask the calculator to compute the value of $1/2 - 1/6$, do you need the answer to come out in the form $1/3$, or is it OK if the answer is $0.33333333$ (approximately, but not exactly $1/3$)? – David K Jul 04 '14 at 00:02
  • You may like to use Microsoft Mathematics. – Kushashwa Ravi Shrimali Jul 04 '14 at 00:34
  • You seem to be asking for computations in the field $\mathbb Q$ of rational numbers. To do these, you’d have to be able to handle pairs (num, denom) of integers, and be able to reduce, by finding the greatest common divisor of the pair. Others can tell you whether there’s a calculator now available that will do that for you. – Lubin Jul 04 '14 at 01:07
  • Are there calculators that return LCMs and GCDs? – Michael Hardy Jul 04 '14 at 03:07
  • @MichaelHardy Not that I'm aware - but there are online calculator tools. The gcd is quite easy to calculate with the Euclidean algorithm though (just iterated division keeping only the remainder). And the lcm can be worked out by dividing the product by the gcd. – Deepak Jul 04 '14 at 05:06

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Depends on how much "thinking" you want to do. If you don't mind figuring out things like the least common multiple of the denominators of a set of unlike fractions before adding or subtracting them, etc., of course you can work with pretty much any calculator.

But if you want an immediate answer without any extra thought or scratch-work, you need a calculator that can handle fractions. Note that not all scientific calculators can handle fractions natively. The ones that can have a special fraction key, e.g. the Casio that I used a long time ago in school had an "a b/c" key that allowed you to enter fractions. They would be displayed as two numbers (numerator and denominator) separated by a sort of reversed L shape. You could do any calculation you wanted with them. You could also convert between improper and mixed fractions using the same key, if I recall correctly.

The (otherwise excellent) free version of RealCalc for Android phones doesn't allow fraction computation. But I believe the paid upgrade does. Just FYI, because lots of people don't bother with dedicated scientific calculators nowadays with the easy availability of powerful phones with great scientific and mathematical apps.

Deepak
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For any two fractions $\dfrac{a}{b}, \dfrac{c}{d}$, do:

  1. Multiply both by $bd$ and enter those numbers into the calculator.
  2. Operate on the two numbers from step 1.
  3. Divide the result by $bd$ on paper for an exact answer or on calculator for a decimal expansion approximation.
Daniel Donnelly
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Yes. You need a scientific calculator.

Try the "C****" brand and model number "fx-50FH". It has a fraction calculating button signified by "a b/c".

To calculate, for example, (1/2) + (1/4), just punch in 1 "a b/c" 2 + 1 "a b/c" 4 and EXEecute. It returns 3 "a special symbol" 4 meaning 3/4.

Mick
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