Compare 21/30 and 18/9, Which fraction is greater?

Compare 21/30 and 18/9

1^st number: 21/30, 2^nd number: 2 0/9

21/30 is smaller than 18/9

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90

Next, find the equivalent fraction of both fractional numbers with denominator 90
For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90
Likewise, for the 2nd fraction, since 9 × 10 = 90,
18/9 = 18 × 10/9 × 10 = 180/90
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
63/90 < 180/90 or 21/30 < 18/9

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