Compare 20/81 and 84/72
1st number: 20/81, 2nd number: 1 12/72
20/81 is smaller than 84/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 72 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Likewise, for the 2nd fraction, since 72 × 9 = 648,
84/72 = 84 × 9/72 × 9 = 756/648 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 160/648 < 756/648 or 20/81 < 84/72
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