Subtract 42/21 from 1/2
1st number: 1/2, 2nd number: 2 0/21
1/2 - 42/21 is -3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
1/2 = 1 × 21/2 × 21 = 21/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Subtract the two like fractions:
21/42 - 84/42 = 21 - 84/42 = -63/42 - After reducing the fraction, the answer is -3/2
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