Subtract 28/80 from 20/7, Solve 2 6/7

Subtract 28/80 from 20/7

1^st number: 2 6/7, 2^nd number: 28/80

20/7 - 28/80 is 351/140.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 80 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 7 × 80 = 560,
20/7 = 20 × 80/7 × 80 = 1600/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
28/80 = 28 × 7/80 × 7 = 196/560
Subtract the two like fractions:
1600/560 - 196/560 = 1600 - 196/560 = 1404/560
After reducing the fraction, the answer is 351/140
In mixed form: 271/140

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