Compare 90/21 and 80/18
1st number: 4 6/21, 2nd number: 4 8/18
90/21 is smaller than 80/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
80/18 = 80 × 7/18 × 7 = 560/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 540/126 < 560/126 or 90/21 < 80/18
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