Compare 3/40 and 20/21
3/40 is smaller than 20/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
3/40 = 3 × 21/40 × 21 = 63/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
20/21 = 20 × 40/21 × 40 = 800/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/840 < 800/840 or 3/40 < 20/21
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