Subtract 4/21 from 3/8
3/8 - 4/21 is 31/168.
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,
3/8 = 3 × 21/8 × 21 = 63/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
4/21 = 4 × 8/21 × 8 = 32/168 - Subtract the two like fractions:
63/168 - 32/168 = 63 - 32/168 = 31/168
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