Compare 18/9 and 72/21
1st number: 2 0/9, 2nd number: 3 9/21
18/9 is smaller than 72/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
18/9 = 18 × 7/9 × 7 = 126/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 126/63 < 216/63 or 18/9 < 72/21
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