Subtract 9/8 from 21/27
1st number: 21/27, 2nd number: 1 1/8
21/27 - 9/8 is -25/72.
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,
9/8 = 9 × 27/8 × 27 = 243/216 - Subtract the two like fractions:
168/216 - 243/216 = 168 - 243/216 = -75/216 - After reducing the fraction, the answer is -25/72
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