Compare 7/80 and 21/81
7/80 is smaller than 21/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
7/80 = 7 × 81/80 × 81 = 567/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
21/81 = 21 × 80/81 × 80 = 1680/6480 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 567/6480 < 1680/6480 or 7/80 < 21/81
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