Working with fractions can be very tricky. Sure, it's all basic mathematics, but there's that slash and those numbers on top and on the bottom. Things need to be converted and simplified, which further complicates matters.
Try these tips to make dealing with fractions easier.
Instant Lowest Common Denominator
Whenever you add or subtract fractions, you first need to find the lowest common denominator, so that you're dealing in equal amounts. Subtracting 1/5 from 1/2 doesn't yield 1/3, it yields 3/10.
The fastest way to find the lowest common denominator is to simply multiply the denominators by one another. For example, if you have 1/5 and 1/2, multiply 5 x 2 to get 10. Then you simply multiply the numerator by it's opposite denominator (2 x 1 for 1/5, which equals 2/10, and 5 x 1 for 1/2, which equals 5/10). To finish the example, 5/10 - 2/10 = 3/10.
This trick works with any fractions you encounter. Be sure to see if you can reduce your final answer to a simpler fraction.
Fixing Oversized Numerators
One of the rules of fractions is that numerators can never be larger than denominators. When the numerator is larger, that means there's a whole number that can be represented. For example, if you get 8/2 as a result, the real answer is 4. If you get 9/2 as a result, the answer is 4 1/2.
Simple division lets you pull the whole numbers out of these top-heavy fractions. Remember that the slash between the numerator and the denominator is a division symbol. All you need to do is divide the denominator into the numerator.
For example, say your result is 49/3. To get the whole number, you divide 49 by 3. The whole number is 16, with a remainder of 1. Instead of solving for that remainder, you simply use it as the new numerator for your fraction. Thus, 49/3 can be reduced to 16 1/3.
It can be faster to do the division before you simplify a fraction. Say you get 48/32 as a result. If you divide 48 by 32, you get 1 and 16/32, which easily simplifies to 1 1/2. If you'd simplified the fraction first, you would have divided both numbers by 16 to get 3/2, arriving at the same result of 1 1/2.
Try these tricks the next time you're working with fractions and you'll see how simple the math can be.
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