Compare 12/15 and 21/40
12/15 is greater than 21/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
12/15 = 12 × 8/15 × 8 = 96/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 96/120 > 63/120 or 12/15 > 21/40
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