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Chapter 9 · Questions · page 47 of 68

How do you simplify a fraction?

Short answerDivide the top and bottom by their greatest common factor. 18/24 becomes 3/4 after dividing both by 6.

levelPre-algebra
standard4.NF.A.1
practiceFraction operations

A fraction is in simplest form when the top and bottom share no factor except 1. Dividing both by the same number does not change the value, only how it is written.

How to use it

  1. Find the largest number that divides both the top and the bottom.
  2. Divide both by it.
  3. If you used a smaller common factor, repeat until nothing more divides both.

Example

1824=18÷624÷6=34\frac{18}{24} = \frac{18 \div 6}{24 \div 6} = \frac{3}{4}
1230=25\frac{12}{30} = \frac{2}{5}
1421=23\frac{14}{21} = \frac{2}{3}

Where it goes wrong

  • Dividing only the top, or only the bottom.
  • Stopping early: 12/30 to 6/15 is a step, not the end.

Related

Equivalent fractions and simplest formWhat a fraction is
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