Subtract 96/42 from 21/40, Solve 21/40

Subtract 96/42 from 21/40

1^st number: 21/40, 2^nd number: 2 12/42

21/40 - 96/42 is -493/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
96/42 = 96 × 20/42 × 20 = 1920/840
Subtract the two like fractions:
441/840 - 1920/840 = 441 - 1920/840 = -1479/840
After reducing the fraction, the answer is -493/280

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