Subtract 75/42 from 3/40, Solve 3/40

Subtract 75/42 from 3/40

1^st number: 3/40, 2^nd number: 1 33/42

3/40 - 75/42 is -479/280.

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,
3/40 = 3 × 21/40 × 21 = 63/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
75/42 = 75 × 20/42 × 20 = 1500/840
Subtract the two like fractions:
63/840 - 1500/840 = 63 - 1500/840 = -1437/840
After reducing the fraction, the answer is -479/280

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