Subtract 28/7 from 7/80, Solve 7/80

Subtract 28/7 from 7/80

1^st number: 7/80, 2^nd number: 4 0/7

7/80 - 28/7 is -313/80.

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

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
7/80 = 7 × 7/80 × 7 = 49/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
28/7 = 28 × 80/7 × 80 = 2240/560
Subtract the two like fractions:
49/560 - 2240/560 = 49 - 2240/560 = -2191/560
After reducing the fraction, the answer is -313/80

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