Subtract 81/35 from 21/42
1st number: 21/42, 2nd number: 2 11/35
21/42 - 81/35 is -127/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
81/35 = 81 × 6/35 × 6 = 486/210 - Subtract the two like fractions:
105/210 - 486/210 = 105 - 486/210 = -381/210 - After reducing the fraction, the answer is -127/70
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