Compare 3/21 and 5/7
3/21 is smaller than 5/7
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
3/21 = 3 × 1/21 × 1 = 3/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 3/21 < 15/21 or 3/21 < 5/7
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