Subtract 4/6 from 20/21
20/21 - 4/6 is 2/7.
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,
20/21 = 20 × 2/21 × 2 = 40/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
4/6 = 4 × 7/6 × 7 = 28/42 - Subtract the two like fractions:
40/42 - 28/42 = 40 - 28/42 = 12/42 - After reducing the fraction, the answer is 2/7
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