Compare 18/21 and 20/18
1st number: 18/21, 2nd number: 1 2/18
18/21 is smaller than 20/18
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,
18/21 = 18 × 6/21 × 6 = 108/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 108/126 < 140/126 or 18/21 < 20/18
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