Subtract 81/42 from 9/8
1st number: 1 1/8, 2nd number: 1 39/42
9/8 - 81/42 is -45/56.
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,
9/8 = 9 × 21/8 × 21 = 189/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
81/42 = 81 × 4/42 × 4 = 324/168 - Subtract the two like fractions:
189/168 - 324/168 = 189 - 324/168 = -135/168 - After reducing the fraction, the answer is -45/56
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