Compare 21/72 and 5/81
21/72 is greater than 5/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
21/72 = 21 × 9/72 × 9 = 189/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
5/81 = 5 × 8/81 × 8 = 40/648 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 189/648 > 40/648 or 21/72 > 5/81
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