Subtract 10/20 from 21/27
21/27 - 10/20 is 5/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 20 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 27 × 20 = 540,
21/27 = 21 × 20/27 × 20 = 420/540 - Likewise, for the 2nd fraction, since 20 × 27 = 540,
10/20 = 10 × 27/20 × 27 = 270/540 - Subtract the two like fractions:
420/540 - 270/540 = 420 - 270/540 = 150/540 - After reducing the fraction, the answer is 5/18
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