Subtract 81/8 from 42/70
1st number: 42/70, 2nd number: 10 1/8
42/70 - 81/8 is -381/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 8 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
42/70 = 42 × 4/70 × 4 = 168/280 - Likewise, for the 2nd fraction, since 8 × 35 = 280,
81/8 = 81 × 35/8 × 35 = 2835/280 - Subtract the two like fractions:
168/280 - 2835/280 = 168 - 2835/280 = -2667/280 - After reducing the fraction, the answer is -381/40
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