Subtract 18/8 from 21/70
1st number: 21/70, 2nd number: 2 2/8
21/70 - 18/8 is -39/20.
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,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 8 × 35 = 280,
18/8 = 18 × 35/8 × 35 = 630/280 - Subtract the two like fractions:
84/280 - 630/280 = 84 - 630/280 = -546/280 - After reducing the fraction, the answer is -39/20
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