Compare 42/80 and 90/18, Which fraction is greater?

Compare 42/80 and 90/18

1^st number: 42/80, 2^nd number: 5 0/18

42/80 is smaller than 90/18

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720
Likewise, for the 2nd fraction, since 18 × 40 = 720,
90/18 = 90 × 40/18 × 40 = 3600/720
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
378/720 < 3600/720 or 42/80 < 90/18

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