Subtract 45/49 from 21/42
21/42 - 45/49 is -41/98.
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,
21/42 = 21 × 7/42 × 7 = 147/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
45/49 = 45 × 6/49 × 6 = 270/294 - Subtract the two like fractions:
147/294 - 270/294 = 147 - 270/294 = -123/294 - After reducing the fraction, the answer is -41/98
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