Compare 81/21 and 30/20
1st number: 3 18/21, 2nd number: 1 10/20
81/21 is greater than 30/20
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,
81/21 = 81 × 20/21 × 20 = 1620/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
30/20 = 30 × 21/20 × 21 = 630/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 1620/420 > 630/420 or 81/21 > 30/20
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