Compare 18/21 and 28/40
18/21 is greater than 28/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
18/21 = 18 × 40/21 × 40 = 720/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
28/40 = 28 × 21/40 × 21 = 588/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 720/840 > 588/840 or 18/21 > 28/40
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