Compare 21/42 and 15/72
21/42 is greater than 15/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
15/72 = 15 × 7/72 × 7 = 105/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 252/504 > 105/504 or 21/42 > 15/72
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