Compare 21/30 and 30/18
1st number: 21/30, 2nd number: 1 12/18
21/30 is smaller than 30/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
30/18 = 30 × 5/18 × 5 = 150/90 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/90 < 150/90 or 21/30 < 30/18
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