Subtract 21/42 from 1/8
1/8 - 21/42 is -3/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
1/8 = 1 × 21/8 × 21 = 21/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Subtract the two like fractions:
21/168 - 84/168 = 21 - 84/168 = -63/168 - After reducing the fraction, the answer is -3/8
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