Subtract 7/21 from 2/8
2/8 - 7/21 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
2/8 = 2 × 21/8 × 21 = 42/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
7/21 = 7 × 8/21 × 8 = 56/168 - Subtract the two like fractions:
42/168 - 56/168 = 42 - 56/168 = -14/168 - After reducing the fraction, the answer is -1/12
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