Compare 4/5 and 54/21, Which fraction is greater?

Compare 4/5 and 54/21

1^st number: 4/5, 2^nd number: 2 12/21

4/5 is smaller than 54/21

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,
4/5 = 4 × 21/5 × 21 = 84/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
54/21 = 54 × 5/21 × 5 = 270/105
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
84/105 < 270/105 or 4/5 < 54/21

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