TenMarks teaches you how to represent decimals as fractions.
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Learn about Fraction Equivalents of Decimals Let’s learn how to write the fraction equivalents of decimals when the whole number part is a nonzero number. The example we’ll use is -1.75. As you can see, this is the decimal part and this is the whole number part. If the whole number part is not zero as in this example, we need to follow one extra step. So, the steps we’ll follow are Step 1, we will write this number down, write this decimal as a whole number plus the decimal part. Step 2 is we convert the decimal part into a fraction and the way we do that, Step 2a, we write the numerator equals the decimal part without the decimal spot, without the decimal point and Step 2b is we write the denominator equals 1 followed by as many zeros as there are digits after the decimal. Let’s actually use these steps. Step 1, the number is -1.72. This is the same as –(1 + 0.75). All I did was break it down in two, 1.75 = 1 + .75. This is the decimal part. If I convert this to fraction, we follow this rule, 2a, write the decimal or without the decimal, so I just removed the decimal and the denominator is one followed by as many zeros as there are digits after the decimal point. After the decimal point, we’ve got two digits, so I put two zeros. So, .75 is the same as 75/100 which is the same as, I can divide by their GCF which is 25, which gives me ¾. So now, I can write this as –(1 + 3/4) okay? The last thing we do is if it’s -1 + 3/4, we can remove the plus sign and just write it this way. The final answer is -1 3/4. The key thing we’ve covered in this track is the steps that we followed to convert a decimal into a fraction. We take the whole number part and the decimal part. Separate them out. The whole number part is 1 and the decimal part is .75. Convert the decimal part into a fraction by writing the numerator as 75, remove the decimal and the denominator becomes one followed by as many zeros as there were digits after the decimal point that gives you 75/100, in simplest terms that’s 3/4. So, what we’re left with is the whole number part plus the fraction part. The decimal part was converted to the fraction part and now I can just combine those, -1 3/4.