Subtract 12/21 from 3/8
3/8 - 12/21 is -11/56.
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,
3/8 = 3 × 21/8 × 21 = 63/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
12/21 = 12 × 8/21 × 8 = 96/168 - Subtract the two like fractions:
63/168 - 96/168 = 63 - 96/168 = -33/168 - After reducing the fraction, the answer is -11/56
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