Subtract 42/21 from 8/42
1st number: 8/42, 2nd number: 2 0/21
8/42 - 42/21 is -38/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
8/42 = 8 × 1/42 × 1 = 8/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Subtract the two like fractions:
8/42 - 84/42 = 8 - 84/42 = -76/42 - After reducing the fraction, the answer is -38/21
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