Subtract 28/42 from 8/21
8/21 - 28/42 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
8/21 = 8 × 2/21 × 2 = 16/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42 - Subtract the two like fractions:
16/42 - 28/42 = 16 - 28/42 = -12/42 - After reducing the fraction, the answer is -2/7
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