Compare 21/84 and 15/45
21/84 is smaller than 15/45
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
15/45 = 15 × 28/45 × 28 = 420/1260 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 315/1260 < 420/1260 or 21/84 < 15/45
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