Subtract 81/14 from 21/42
1st number: 21/42, 2nd number: 5 11/14
21/42 - 81/14 is -37/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 14 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 14 × 3 = 42,
81/14 = 81 × 3/14 × 3 = 243/42 - Subtract the two like fractions:
21/42 - 243/42 = 21 - 243/42 = -222/42 - After reducing the fraction, the answer is -37/7
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