Subtract 28/12 from 40/21
1st number: 1 19/21, 2nd number: 2 4/12
40/21 - 28/12 is -3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84 - Subtract the two like fractions:
160/84 - 196/84 = 160 - 196/84 = -36/84 - After reducing the fraction, the answer is -3/7
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