Subtract 2/21 from 81/42
1st number: 1 39/42, 2nd number: 2/21
81/42 - 2/21 is 11/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
2/21 = 2 × 2/21 × 2 = 4/42 - Subtract the two like fractions:
81/42 - 4/42 = 81 - 4/42 = 77/42 - After reducing the fraction, the answer is 11/6
- In mixed form: 15/6
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