Compare 30/21 and 21/18
1st number: 1 9/21, 2nd number: 1 3/18
30/21 is greater than 21/18
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,
30/21 = 30 × 6/21 × 6 = 180/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 180/126 > 147/126 or 30/21 > 21/18
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