Compare 21/40 and 30/80
21/40 is greater than 30/80
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
21/40 = 21 × 2/40 × 2 = 42/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/80 > 30/80 or 21/40 > 30/80
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