Subtract 40/84 from 15/42
15/42 - 40/84 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
15/42 = 15 × 2/42 × 2 = 30/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Subtract the two like fractions:
30/84 - 40/84 = 30 - 40/84 = -10/84 - After reducing the fraction, the answer is -5/42
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