Compare 21/30 and 12/15
21/30 is smaller than 12/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 15 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Likewise, for the 2nd fraction, since 15 × 2 = 30,
12/15 = 12 × 2/15 × 2 = 24/30 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 21/30 < 24/30 or 21/30 < 12/15
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