Compare 21/18 and 72/20
1st number: 1 3/18, 2nd number: 3 12/20
21/18 is smaller than 72/20
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/180 < 648/180 or 21/18 < 72/20
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