Compare 7/30 and 42/21
1st number: 7/30, 2nd number: 2 0/21
7/30 is smaller than 42/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
7/30 = 7 × 7/30 × 7 = 49/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 49/210 < 420/210 or 7/30 < 42/21
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