Subtract 20/28 from 3/9
3/9 - 20/28 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 28 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 9 × 28 = 252,
3/9 = 3 × 28/9 × 28 = 84/252 - Likewise, for the 2nd fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252 - Subtract the two like fractions:
84/252 - 180/252 = 84 - 180/252 = -96/252 - After reducing the fraction, the answer is -8/21
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