Subtract 30/42 from 12/18
12/18 - 30/42 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
30/42 = 30 × 3/42 × 3 = 90/126 - Subtract the two like fractions:
84/126 - 90/126 = 84 - 90/126 = -6/126 - After reducing the fraction, the answer is -1/21
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