In the arena of mathematics, the term "dilate" applies to an action in which you change the size of a term or figure based on a set amount. This amount is known as the scale factor. When you dilate a fraction, you increase or decrease its size as determined by the scale factor. You must use multiplication in order to perform this type of calculation. You might see this type of problem in a middle school, high school or college math or geometry course.

Write down the fraction.

Choose a scale factor or use one that is dictated in your assignment. For example, you might want to dilate the fraction 2/3 with a scale factor of 3. This means that you are making the fraction three times larger.

Multiply the scale factor times the fraction. In this case, you would multiply 3 times 2/3. Write 3 as the fraction 3/1. Then multiply the numerators (3 and 2), as well as the denominators (1 and 3). This gives you an answer of 6/3, which can be simplified to 2.
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