Compare 3/15 and 21/30
3/15 is smaller than 21/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 15 × 2 = 30,
3/15 = 3 × 2/15 × 2 = 6/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 6/30 < 21/30 or 3/15 < 21/30
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