Subtract 21/8 from 6/42
1st number: 6/42, 2nd number: 2 5/8
6/42 - 21/8 is -139/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
6/42 = 6 × 4/42 × 4 = 24/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
24/168 - 441/168 = 24 - 441/168 = -417/168 - After reducing the fraction, the answer is -139/56
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