Subtract 6/7 from 21/63
21/63 - 6/7 is -11/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 7 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63 - Likewise, for the 2nd fraction, since 7 × 9 = 63,
6/7 = 6 × 9/7 × 9 = 54/63 - Subtract the two like fractions:
21/63 - 54/63 = 21 - 54/63 = -33/63 - After reducing the fraction, the answer is -11/21
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