Compare 20/21 and 12/18
20/21 is greater than 12/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 120/126 > 84/126 or 20/21 > 12/18
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