Compare 7/90 and 21/81
7/90 is smaller than 21/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
7/90 = 7 × 9/90 × 9 = 63/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
21/81 = 21 × 10/81 × 10 = 210/810 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/810 < 210/810 or 7/90 < 21/81
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