Compare 70/21 and 90/81
1st number: 3 7/21, 2nd number: 1 9/81
70/21 is greater than 90/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
70/21 = 70 × 27/21 × 27 = 1890/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 1890/567 > 630/567 or 70/21 > 90/81
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