Compare 81/21 and 45/72
1st number: 3 18/21, 2nd number: 45/72
81/21 is greater than 45/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
81/21 = 81 × 24/21 × 24 = 1944/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 1944/504 > 315/504 or 81/21 > 45/72
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