Subtract 81/21 from 20/6
1st number: 3 2/6, 2nd number: 3 18/21
20/6 - 81/21 is -11/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 6 × 7 = 42,
20/6 = 20 × 7/6 × 7 = 140/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Subtract the two like fractions:
140/42 - 162/42 = 140 - 162/42 = -22/42 - After reducing the fraction, the answer is -11/21
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