Subtract 21/70 from 7/40
7/40 - 21/70 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
7/40 = 7 × 7/40 × 7 = 49/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Subtract the two like fractions:
49/280 - 84/280 = 49 - 84/280 = -35/280 - After reducing the fraction, the answer is -1/8
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