Compare 15/80 and 30/21
1st number: 15/80, 2nd number: 1 9/21
15/80 is smaller than 30/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
15/80 = 15 × 21/80 × 21 = 315/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
30/21 = 30 × 80/21 × 80 = 2400/1680 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 315/1680 < 2400/1680 or 15/80 < 30/21
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