Subtract 28/70 from 1/80, Solve 1/80

Subtract 28/70 from 1/80

1/80 - 28/70 is -31/80.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
1/80 = 1 × 7/80 × 7 = 7/560
Likewise, for the 2nd fraction, since 70 × 8 = 560,
28/70 = 28 × 8/70 × 8 = 224/560
Subtract the two like fractions:
7/560 - 224/560 = 7 - 224/560 = -217/560
After reducing the fraction, the answer is -31/80

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