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How to Make a Number a Fraction

Fractions contain a numerator on top and a denominator on bottom, separated by a horizontal line that represents division. A proper fraction has a smaller numerator than denominator and the division will result in a decimal smaller than 1. An improper fraction has a larger numerator than denominator and the division can result in a whole number or a decimal larger than 1. Mixed numbers and decimals can be converted back to fractional form. Converting a whole number to a fraction requires only that the whole number be placed above a denominator of 1. For example, 5 = 5/1.

Instructions

- 1
  Convert a mixed number, which features a whole number followed by a fraction, by multiplying the whole number by the denominator and adding the numerator. Write the answer as the new numerator above the original denominator. Use 1 and 4/5 as an example: 1 * 5 = 5 + 4 = 9 so the final fraction is 9/5.
- 2
  Count the number of decimal places in a terminating, or non-repeating, decimal to determine what multiple of 10 to make the denominator. Simplify the result. Use 1.6 as an example. Write the denominator as 10 since there is only one decimal place and make the numerator the number without the decimal point: 16/10. Simplify: 8/5.
- 3
  Convert a repeating decimal to fraction form by creating an equation that multiplies "x" by a 10 value with the same number of zeros as the repeating digits in the decimal. Use the repeating decimal 0.8333... as an example. Set up the left side of the equation as 10x since only one digit repeats in the decimal. Use the decimal multiplied by 10 as the right side of the equation, making the whole equation: 10x = 8.333.
  
  Subtract the original information, x = 0.8333, from the new equation: 10x - x = 8.333 - 0.8333 becomes 9x = 7.4997 or 9x = 7.5 (rounded). Convert the decimal to a fraction using the techniques in Step 2: 75 / 10 = 15/2. Place back in the equation: 9x = 15/2. Divide both sides by 9 (or multiply by 1/9): x = (15/2) * (1/9) = 15/18. Simplify: 15/18 = 5/6.

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