Compare 7/20 and 12/21
7/20 is smaller than 12/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
12/21 = 12 × 20/21 × 20 = 240/420 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 147/420 < 240/420 or 7/20 < 12/21
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