Compare 81/21 and 20/30
1st number: 3 18/21, 2nd number: 20/30
81/21 is greater than 20/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 810/210 > 140/210 or 81/21 > 20/30
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