Subtract 8/40 from 4/42
4/42 - 8/40 is -11/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
4/42 = 4 × 20/42 × 20 = 80/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
8/40 = 8 × 21/40 × 21 = 168/840 - Subtract the two like fractions:
80/840 - 168/840 = 80 - 168/840 = -88/840 - After reducing the fraction, the answer is -11/105
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