Subtract 21/30 from 20/27
20/27 - 21/30 is 11/270.
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,
20/27 = 20 × 10/27 × 10 = 200/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
21/30 = 21 × 9/30 × 9 = 189/270 - Subtract the two like fractions:
200/270 - 189/270 = 200 - 189/270 = 11/270
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