Subtract 81/42 from 21/2
1st number: 10 1/2, 2nd number: 1 39/42
21/2 - 81/42 is 60/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 42 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 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Subtract the two like fractions:
441/42 - 81/42 = 441 - 81/42 = 360/42 - After reducing the fraction, the answer is 60/7
- In mixed form: 84/7
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