Subtract 21/81 from 7/32
7/32 - 21/81 is -35/864.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 32 and 81 is 2592
Next, find the equivalent fraction of both fractional numbers with denominator 2592 - For the 1st fraction, since 32 × 81 = 2592,
7/32 = 7 × 81/32 × 81 = 567/2592 - Likewise, for the 2nd fraction, since 81 × 32 = 2592,
21/81 = 21 × 32/81 × 32 = 672/2592 - Subtract the two like fractions:
567/2592 - 672/2592 = 567 - 672/2592 = -105/2592 - After reducing the fraction, the answer is -35/864
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