Subtract 8/9 from 7/21
7/21 - 8/9 is -5/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
7/21 = 7 × 3/21 × 3 = 21/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
8/9 = 8 × 7/9 × 7 = 56/63 - Subtract the two like fractions:
21/63 - 56/63 = 21 - 56/63 = -35/63 - After reducing the fraction, the answer is -5/9
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