Subtract 12/18 from 40/42
40/42 - 12/18 is 2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
40/42 = 40 × 3/42 × 3 = 120/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126 - Subtract the two like fractions:
120/126 - 84/126 = 120 - 84/126 = 36/126 - After reducing the fraction, the answer is 2/7
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