Subtract 28/8 from 42/84
1st number: 42/84, 2nd number: 3 4/8
42/84 - 28/8 is -3/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
42/84 = 42 × 2/84 × 2 = 84/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
28/8 = 28 × 21/8 × 21 = 588/168 - Subtract the two like fractions:
84/168 - 588/168 = 84 - 588/168 = -504/168 - After reducing the fraction, the answer is -3/1
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