Compare 21/84 and 5/15
21/84 is smaller than 5/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
5/15 = 5 × 28/15 × 28 = 140/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/420 < 140/420 or 21/84 < 5/15
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