Compare 30/21 and 42/28
1st number: 1 9/21, 2nd number: 1 14/28
30/21 is smaller than 42/28
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
42/28 = 42 × 3/28 × 3 = 126/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 120/84 < 126/84 or 30/21 < 42/28
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