Compare 21/20 and 18/21
1st number: 1 1/20, 2nd number: 18/21
21/20 is greater than 18/21
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,
21/20 = 21 × 21/20 × 21 = 441/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 441/420 > 360/420 or 21/20 > 18/21
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