Compare 20/80 and 81/90
20/80 is smaller than 81/90
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
20/80 = 20 × 9/80 × 9 = 180/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
81/90 = 81 × 8/90 × 8 = 648/720 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 180/720 < 648/720 or 20/80 < 81/90
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