Subtract 3/42 from 1/40
1/40 - 3/42 is -13/280.
Steps for subtracting fractions
- 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,
1/40 = 1 × 21/40 × 21 = 21/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
3/42 = 3 × 20/42 × 20 = 60/840 - Subtract the two like fractions:
21/840 - 60/840 = 21 - 60/840 = -39/840 - After reducing the fraction, the answer is -13/280
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