Subtract 30/42 from 12/36
12/36 - 30/42 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
12/36 = 12 × 7/36 × 7 = 84/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
30/42 = 30 × 6/42 × 6 = 180/252 - Subtract the two like fractions:
84/252 - 180/252 = 84 - 180/252 = -96/252 - After reducing the fraction, the answer is -8/21
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