Compare 42/10 and 21/3, Which fraction is greater?

Compare 42/10 and 21/3

1^st number: 4 2/10, 2^nd number: 7 0/3

42/10 is smaller than 21/3

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 3 is 30

Next, find the equivalent fraction of both fractional numbers with denominator 30
For the 1st fraction, since 10 × 3 = 30,
42/10 = 42 × 3/10 × 3 = 126/30
Likewise, for the 2nd fraction, since 3 × 10 = 30,
21/3 = 21 × 10/3 × 10 = 210/30
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
126/30 < 210/30 or 42/10 < 21/3

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