Compare 20/12 and 40/21
1st number: 1 8/12, 2nd number: 1 19/21
20/12 is smaller than 40/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 140/84 < 160/84 or 20/12 < 40/21
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