Subtract 40/49 from 18/42
18/42 - 40/49 is -19/49.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294
Next, find the equivalent fraction of both fractional numbers with denominator 294 - For the 1st fraction, since 42 × 7 = 294,
18/42 = 18 × 7/42 × 7 = 126/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
40/49 = 40 × 6/49 × 6 = 240/294 - Subtract the two like fractions:
126/294 - 240/294 = 126 - 240/294 = -114/294 - After reducing the fraction, the answer is -19/49
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