Compare 2/5 and 10/21, Which fraction is greater?

Compare 2/5 and 10/21

2/5 is smaller than 10/21

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
2/5 = 2 × 21/5 × 21 = 42/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
10/21 = 10 × 5/21 × 5 = 50/105
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
42/105 < 50/105 or 2/5 < 10/21

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