Subtract 42/21 from 21/2
1st number: 10 1/2, 2nd number: 2 0/21
21/2 - 42/21 is 17/2.
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,
21/2 = 21 × 21/2 × 21 = 441/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Subtract the two like fractions:
441/42 - 84/42 = 441 - 84/42 = 357/42 - After reducing the fraction, the answer is 17/2
- In mixed form: 81/2
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