Subtract 21/30 from 12/27
12/27 - 21/30 is -23/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 30 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 27 × 10 = 270,
12/27 = 12 × 10/27 × 10 = 120/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
21/30 = 21 × 9/30 × 9 = 189/270 - Subtract the two like fractions:
120/270 - 189/270 = 120 - 189/270 = -69/270 - After reducing the fraction, the answer is -23/90
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