Subtract 27/70 from 18/80, Solve 18/80

Subtract 27/70 from 18/80

18/80 - 27/70 is -9/56.

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,
18/80 = 18 × 7/80 × 7 = 126/560
Likewise, for the 2nd fraction, since 70 × 8 = 560,
27/70 = 27 × 8/70 × 8 = 216/560
Subtract the two like fractions:
126/560 - 216/560 = 126 - 216/560 = -90/560
After reducing the fraction, the answer is -9/56

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