Subtract 28/21 from 21/2
1st number: 10 1/2, 2nd number: 1 7/21
21/2 - 28/21 is 55/6.
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,
28/21 = 28 × 2/21 × 2 = 56/42 - Subtract the two like fractions:
441/42 - 56/42 = 441 - 56/42 = 385/42 - After reducing the fraction, the answer is 55/6
- In mixed form: 91/6
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