Subtract 18/21 from 81/2
1st number: 40 1/2, 2nd number: 18/21
81/2 - 18/21 is 555/14.
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,
81/2 = 81 × 21/2 × 21 = 1701/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Subtract the two like fractions:
1701/42 - 36/42 = 1701 - 36/42 = 1665/42 - After reducing the fraction, the answer is 555/14
- In mixed form: 399/14
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