Compare 3/9 and 15/21
3/9 is smaller than 15/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
3/9 = 3 × 7/9 × 7 = 21/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 21/63 < 45/63 or 3/9 < 15/21
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