Subtract 40/9 from 42/12
1st number: 3 6/12, 2nd number: 4 4/9
42/12 - 40/9 is -17/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
42/12 = 42 × 3/12 × 3 = 126/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
40/9 = 40 × 4/9 × 4 = 160/36 - Subtract the two like fractions:
126/36 - 160/36 = 126 - 160/36 = -34/36 - After reducing the fraction, the answer is -17/18
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