Subtract 28/80 from 12/9, Solve 1 3/9

Subtract 28/80 from 12/9

1^st number: 1 3/9, 2^nd number: 28/80

12/9 - 28/80 is 59/60.

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

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 9 × 80 = 720,
12/9 = 12 × 80/9 × 80 = 960/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
28/80 = 28 × 9/80 × 9 = 252/720
Subtract the two like fractions:
960/720 - 252/720 = 960 - 252/720 = 708/720
After reducing the fraction, the answer is 59/60

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