Subtract 81/80 from 30/12, Solve 2 6/12

Subtract 81/80 from 30/12

1^st number: 2 6/12, 2^nd number: 1 1/80

30/12 - 81/80 is 119/80.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 12 × 20 = 240,
30/12 = 30 × 20/12 × 20 = 600/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
81/80 = 81 × 3/80 × 3 = 243/240
Subtract the two like fractions:
600/240 - 243/240 = 600 - 243/240 = 357/240
After reducing the fraction, the answer is 119/80
In mixed form: 139/80

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