Compare 12/42 and 21/72
12/42 is smaller than 21/72
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,
12/42 = 12 × 12/42 × 12 = 144/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 144/504 < 147/504 or 12/42 < 21/72
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