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