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