Compare 21/30 and 28/20
1st number: 21/30, 2nd number: 1 8/20
21/30 is smaller than 28/20
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
28/20 = 28 × 3/20 × 3 = 84/60 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/60 < 84/60 or 21/30 < 28/20
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