Subtract 16/21 from 81/2
1st number: 40 1/2, 2nd number: 16/21
81/2 - 16/21 is 1669/42.
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,
16/21 = 16 × 2/21 × 2 = 32/42 - Subtract the two like fractions:
1701/42 - 32/42 = 1701 - 32/42 = 1669/42 - In mixed form: 3931/42
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