Compare 20/40 and 10/21
20/40 is greater than 10/21
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,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
10/21 = 10 × 40/21 × 40 = 400/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 420/840 > 400/840 or 20/40 > 10/21
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