Subtract 36/8 from 81/42
1st number: 1 39/42, 2nd number: 4 4/8
81/42 - 36/8 is -18/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
81/42 = 81 × 4/42 × 4 = 324/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
36/8 = 36 × 21/8 × 21 = 756/168 - Subtract the two like fractions:
324/168 - 756/168 = 324 - 756/168 = -432/168 - After reducing the fraction, the answer is -18/7
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