One skill that helps students succeed in math classes is the ability to move easily between fractions, decimals, and ratios. Nevertheless, this can be challenging to learn. Many calculators will present answers in the form of mixed numbers, e.g., 2.5. However, if a student is working through a multiple-choice problem where the numbers are presented in fractional form, or needs to answer the problem in fractional form for other reasons, she may find it challenging to convert it. Working step-by-step will allow you to estimate fractions from a mixed numbers calculator.
Work out your problem on your calculator as normal. Type in the numbers and the function, and solve it as you usually would, examining the answer. For example, you might have 1.25 x 2 = 2.5, which is a mixed number.
Separate the whole number from the decimal in your answer. Using the above example, forget about 2 for the moment and focus on the .5 that follows it.
Convert the decimal into a fraction. To do this, envision which numbers would divide to give you the decimal at hand. Estimating fractions can work well here, knowing that 1/2 is .5, that 1/3 is .33, and that 1/4 is .25. Therefore, if you have a decimal of .125, you can view it as half of 1/4, or 1/8.
Return to your whole number, putting it in fractional form. To do this, make the numerator and the denominator the same as the resulting denominator from the fraction you have just found. In the earlier example, if you found that .5 turned into 1/2, you would also need to put 2 in terms of halves. To do this, start by taking 1 as a fraction expressed in halves, which will have the same numerator and denominator: 2/2. Now, multiply the numerator by the original whole number, or 2, to get 4/2.
Add the two resulting fractions together by adding the numerators together and keeping the denominators the same. Therefore, in our example, 1/2 + 4/2 = 5/2, the final fractional answer to the problem.
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