Subtract 7/80 from 12/9, Solve 1 3/9

Subtract 7/80 from 12/9

1^st number: 1 3/9, 2^nd number: 7/80

12/9 - 7/80 is 299/240.

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,
7/80 = 7 × 9/80 × 9 = 63/720
Subtract the two like fractions:
960/720 - 63/720 = 960 - 63/720 = 897/720
After reducing the fraction, the answer is 299/240
In mixed form: 159/240

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