Compare 81/21 and 20/9
1st number: 3 18/21, 2nd number: 2 2/9
81/21 is greater than 20/9
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
81/21 = 81 × 3/21 × 3 = 243/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
20/9 = 20 × 7/9 × 7 = 140/63 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 243/63 > 140/63 or 81/21 > 20/9
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