Subtract 40/18 from 27/21, Solve 1 6/21

Subtract 40/18 from 27/21

1^st number: 1 6/21, 2^nd number: 2 4/18

27/21 - 40/18 is -59/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
27/21 = 27 × 6/21 × 6 = 162/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
40/18 = 40 × 7/18 × 7 = 280/126
Subtract the two like fractions:
162/126 - 280/126 = 162 - 280/126 = -118/126
After reducing the fraction, the answer is -59/63

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