Subtract 7/8 from 21/27
21/27 - 7/8 is -7/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 8 is 216
Next, find the equivalent fraction of both fractional numbers with denominator 216 - For the 1st fraction, since 27 × 8 = 216,
21/27 = 21 × 8/27 × 8 = 168/216 - Likewise, for the 2nd fraction, since 8 × 27 = 216,
7/8 = 7 × 27/8 × 27 = 189/216 - Subtract the two like fractions:
168/216 - 189/216 = 168 - 189/216 = -21/216 - After reducing the fraction, the answer is -7/72
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