Subtract 90/8 from 42/70
1st number: 42/70, 2nd number: 11 2/8
42/70 - 90/8 is -213/20.
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,
90/8 = 90 × 35/8 × 35 = 3150/280 - Subtract the two like fractions:
168/280 - 3150/280 = 168 - 3150/280 = -2982/280 - After reducing the fraction, the answer is -213/20
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