Subtract 72/49 from 54/80, Solve 54/80

Subtract 72/49 from 54/80

1^st number: 54/80, 2^nd number: 1 23/49

54/80 - 72/49 is -1557/1960.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 49 is 3920

Next, find the equivalent fraction of both fractional numbers with denominator 3920
For the 1st fraction, since 80 × 49 = 3920,
54/80 = 54 × 49/80 × 49 = 2646/3920
Likewise, for the 2nd fraction, since 49 × 80 = 3920,
72/49 = 72 × 80/49 × 80 = 5760/3920
Subtract the two like fractions:
2646/3920 - 5760/3920 = 2646 - 5760/3920 = -3114/3920
After reducing the fraction, the answer is -1557/1960

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