How do I apply the four operations to Fractions?

When using the four operations (addition, subtraction, multiplication and division) on fractions there are specific methods for each. Multiplication and division are very similar. In order to multiply two fractions, you simply multiply the numerator and denominator together to produce your result. Division is the same method but with one extra step, you flip the second fraction so that the numerator and denominator switch places and then multiply. Addition and subtraction are slightly more complex. FIrstly, you need to check whether the two fractions you want to add/subtract have equivalent denominators. If they do then you simply apply the operation to the numerators of your fractions. If they are not equivalent, you must apply the cross method to produce a new denominator. This method has three parts:1) Multiply both denominators 2) Multiply the denominator of the first fraction with the numerator of the second 3) Multiply the numerator of the first fraction with the denominator of the second. You can then apply the operation on the values produced by steps 2 and 3, and place them above your new denominator to produce your answer. It is called the cross method as you cross-multiply your two fractions to achieve your result.

JP

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