Subtract 27/7 from 18/40, Solve 18/40

Subtract 27/7 from 18/40

1^st number: 18/40, 2^nd number: 3 6/7

18/40 - 27/7 is -477/140.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 40 × 7 = 280,
18/40 = 18 × 7/40 × 7 = 126/280
Likewise, for the 2nd fraction, since 7 × 40 = 280,
27/7 = 27 × 40/7 × 40 = 1080/280
Subtract the two like fractions:
126/280 - 1080/280 = 126 - 1080/280 = -954/280
After reducing the fraction, the answer is -477/140

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