Subtract 21/81 from 1/42
1/42 - 21/81 is -89/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
1/42 = 1 × 27/42 × 27 = 27/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Subtract the two like fractions:
27/1134 - 294/1134 = 27 - 294/1134 = -267/1134 - After reducing the fraction, the answer is -89/378
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