Subtract 21/9 from 21/28
1st number: 21/28, 2nd number: 2 3/9
21/28 - 21/9 is -19/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Subtract the two like fractions:
189/252 - 588/252 = 189 - 588/252 = -399/252 - After reducing the fraction, the answer is -19/12
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