Compare 40/72 and 18/21
40/72 is smaller than 18/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
18/21 = 18 × 24/21 × 24 = 432/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 280/504 < 432/504 or 40/72 < 18/21
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