Subtract 27/14 from 21/18, Solve 1 3/18

Subtract 27/14 from 21/18

1^st number: 1 3/18, 2^nd number: 1 13/14

21/18 - 27/14 is -16/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 14 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126
Likewise, for the 2nd fraction, since 14 × 9 = 126,
27/14 = 27 × 9/14 × 9 = 243/126
Subtract the two like fractions:
147/126 - 243/126 = 147 - 243/126 = -96/126
After reducing the fraction, the answer is -16/21

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