Compare 21/90 and 15/80
21/90 is greater than 15/80
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
15/80 = 15 × 9/80 × 9 = 135/720 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 168/720 > 135/720 or 21/90 > 15/80
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