Compare 12/20 and 9/21
12/20 is greater than 9/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
9/21 = 9 × 20/21 × 20 = 180/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 252/420 > 180/420 or 12/20 > 9/21
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