Subtract 30/7 from 40/12
1st number: 3 4/12, 2nd number: 4 2/7
40/12 - 30/7 is -20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
30/7 = 30 × 12/7 × 12 = 360/84 - Subtract the two like fractions:
280/84 - 360/84 = 280 - 360/84 = -80/84 - After reducing the fraction, the answer is -20/21
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