Subtract 42/84 from 3/9
3/9 - 42/84 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 84 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 9 × 28 = 252,
3/9 = 3 × 28/9 × 28 = 84/252 - Likewise, for the 2nd fraction, since 84 × 3 = 252,
42/84 = 42 × 3/84 × 3 = 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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