Subtract 4/12 from 40/42
40/42 - 4/12 is 13/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
40/42 = 40 × 2/42 × 2 = 80/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
4/12 = 4 × 7/12 × 7 = 28/84 - Subtract the two like fractions:
80/84 - 28/84 = 80 - 28/84 = 52/84 - After reducing the fraction, the answer is 13/21
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