Subtract 70/9 from 28/80, Solve 28/80

Subtract 70/9 from 28/80

1^st number: 28/80, 2^nd number: 7 7/9

28/80 - 70/9 is -1337/180.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
28/80 = 28 × 9/80 × 9 = 252/720
Likewise, for the 2nd fraction, since 9 × 80 = 720,
70/9 = 70 × 80/9 × 80 = 5600/720
Subtract the two like fractions:
252/720 - 5600/720 = 252 - 5600/720 = -5348/720
After reducing the fraction, the answer is -1337/180

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