Compare 6/18 and 20/21
6/18 is smaller than 20/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
6/18 = 6 × 7/18 × 7 = 42/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
20/21 = 20 × 6/21 × 6 = 120/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/126 < 120/126 or 6/18 < 20/21
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