Compare 70/80 and 21/63, Which fraction is greater?

Compare 70/80 and 21/63

70/80 is greater than 21/63

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040

Next, find the equivalent fraction of both fractional numbers with denominator 5040
For the 1st fraction, since 80 × 63 = 5040,
70/80 = 70 × 63/80 × 63 = 4410/5040
Likewise, for the 2nd fraction, since 63 × 80 = 5040,
21/63 = 21 × 80/63 × 80 = 1680/5040
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
4410/5040 > 1680/5040 or 70/80 > 21/63

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