Compare 3/7 and 21/30
3/7 is smaller than 21/30
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 7 × 30 = 210,
3/7 = 3 × 30/7 × 30 = 90/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 90/210 < 147/210 or 3/7 < 21/30
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