Subtract 40/84 from 8/20
8/20 - 40/84 is -8/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
40/84 = 40 × 5/84 × 5 = 200/420 - Subtract the two like fractions:
168/420 - 200/420 = 168 - 200/420 = -32/420 - After reducing the fraction, the answer is -8/105
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