Subtract 9/30 from 21/27
21/27 - 9/30 is 43/90.
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,
21/27 = 21 × 10/27 × 10 = 210/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
9/30 = 9 × 9/30 × 9 = 81/270 - Subtract the two like fractions:
210/270 - 81/270 = 210 - 81/270 = 129/270 - After reducing the fraction, the answer is 43/90
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