Compare 42/8 and 84/21, Which fraction is greater?

Compare 42/8 and 84/21

1^st number: 5 2/8, 2^nd number: 4 0/21

42/8 is greater than 84/21

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
42/8 = 42 × 21/8 × 21 = 882/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
84/21 = 84 × 8/21 × 8 = 672/168
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
882/168 > 672/168 or 42/8 > 84/21

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