Compare 3/18 and 15/21
3/18 is smaller than 15/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
3/18 = 3 × 7/18 × 7 = 21/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
15/21 = 15 × 6/21 × 6 = 90/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 21/126 < 90/126 or 3/18 < 15/21
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