Subtract 5/21 from 1/8
1/8 - 5/21 is -19/168.
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,
1/8 = 1 × 21/8 × 21 = 21/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
5/21 = 5 × 8/21 × 8 = 40/168 - Subtract the two like fractions:
21/168 - 40/168 = 21 - 40/168 = -19/168
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