Subtract 80/42 from 27/18, Solve 1 9/18

Subtract 80/42 from 27/18

1^st number: 1 9/18, 2^nd number: 1 38/42

27/18 - 80/42 is -17/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
27/18 = 27 × 7/18 × 7 = 189/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
80/42 = 80 × 3/42 × 3 = 240/126
Subtract the two like fractions:
189/126 - 240/126 = 189 - 240/126 = -51/126
After reducing the fraction, the answer is -17/42

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