Subtract 21/8 from 54/42
1st number: 1 12/42, 2nd number: 2 5/8
54/42 - 21/8 is -75/56.
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,
54/42 = 54 × 4/42 × 4 = 216/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Subtract the two like fractions:
216/168 - 441/168 = 216 - 441/168 = -225/168 - After reducing the fraction, the answer is -75/56
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