Subtract 8/16 from 8/21
8/21 - 8/16 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 21 × 16 = 336,
8/21 = 8 × 16/21 × 16 = 128/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
8/16 = 8 × 21/16 × 21 = 168/336 - Subtract the two like fractions:
128/336 - 168/336 = 128 - 168/336 = -40/336 - After reducing the fraction, the answer is -5/42
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