Compare 9/12 and 18/21
9/12 is smaller than 18/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
9/12 = 9 × 7/12 × 7 = 63/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/84 < 72/84 or 9/12 < 18/21
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