Compare 12/42 and 20/21
12/42 is smaller than 20/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
12/42 = 12 × 1/42 × 1 = 12/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 12/42 < 40/42 or 12/42 < 20/21
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