Subtract 7/14 from 20/21
20/21 - 7/14 is 19/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 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 14 × 3 = 42,
7/14 = 7 × 3/14 × 3 = 21/42 - Subtract the two like fractions:
40/42 - 21/42 = 40 - 21/42 = 19/42
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