Compare 3/21 and 18/72
3/21 is smaller than 18/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
3/21 = 3 × 24/21 × 24 = 72/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 72/504 < 126/504 or 3/21 < 18/72
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