Compare 21/28 and 30/15
1st number: 21/28, 2nd number: 2 0/15
21/28 is smaller than 30/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
30/15 = 30 × 28/15 × 28 = 840/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 315/420 < 840/420 or 21/28 < 30/15
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