Subtract 81/21 from 4/2
1st number: 2 0/2, 2nd number: 3 18/21
4/2 - 81/21 is -13/7.
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,
4/2 = 4 × 21/2 × 21 = 84/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Subtract the two like fractions:
84/42 - 162/42 = 84 - 162/42 = -78/42 - After reducing the fraction, the answer is -13/7
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