Subtract 21/9 from 40/28
1st number: 1 12/28, 2nd number: 2 3/9
40/28 - 21/9 is -19/21.
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,
40/28 = 40 × 9/28 × 9 = 360/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Subtract the two like fractions:
360/252 - 588/252 = 360 - 588/252 = -228/252 - After reducing the fraction, the answer is -19/21
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