Compare 21/81 and 28/30
21/81 is smaller than 28/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 30 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
21/81 = 21 × 10/81 × 10 = 210/810 - Likewise, for the 2nd fraction, since 30 × 27 = 810,
28/30 = 28 × 27/30 × 27 = 756/810 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/810 < 756/810 or 21/81 < 28/30
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