Compare 70/81 and 21/40
70/81 is greater than 21/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
70/81 = 70 × 40/81 × 40 = 2800/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
21/40 = 21 × 81/40 × 81 = 1701/3240 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 2800/3240 > 1701/3240 or 70/81 > 21/40
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