Compare 30/45 and 21/81
30/45 is greater than 21/81
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
30/45 = 30 × 9/45 × 9 = 270/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 270/405 > 105/405 or 30/45 > 21/81
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