Subtract 21/42 from 12/36
12/36 - 21/42 is -1/6.
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,
21/42 = 21 × 6/42 × 6 = 126/252 - Subtract the two like fractions:
84/252 - 126/252 = 84 - 126/252 = -42/252 - After reducing the fraction, the answer is -1/6
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