Subtract 81/35 from 18/40, Solve 18/40

Subtract 81/35 from 18/40

1^st number: 18/40, 2^nd number: 2 11/35

18/40 - 81/35 is -261/140.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 35 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 35 × 8 = 280,
81/35 = 81 × 8/35 × 8 = 648/280
Subtract the two like fractions:
126/280 - 648/280 = 126 - 648/280 = -522/280
After reducing the fraction, the answer is -261/140

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