Compare 18/21 and 81/5
1st number: 18/21, 2nd number: 16 1/5
18/21 is smaller than 81/5
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
81/5 = 81 × 21/5 × 21 = 1701/105 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 90/105 < 1701/105 or 18/21 < 81/5
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