Subtract 20/6 from 42/21
1st number: 2 0/21, 2nd number: 3 2/6
42/21 - 20/6 is -4/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
20/6 = 20 × 7/6 × 7 = 140/42 - Subtract the two like fractions:
84/42 - 140/42 = 84 - 140/42 = -56/42 - After reducing the fraction, the answer is -4/3
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