Compare 21/36 and 42/80
21/36 is greater than 42/80
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 36 × 20 = 720,
21/36 = 21 × 20/36 × 20 = 420/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 420/720 > 378/720 or 21/36 > 42/80
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