Compare 81/21 and 20/4
1st number: 3 18/21, 2nd number: 5 0/4
81/21 is smaller than 20/4
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
20/4 = 20 × 21/4 × 21 = 420/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 324/84 < 420/84 or 81/21 < 20/4
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