Subtract 15/18 from 42/84
42/84 - 15/18 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
42/84 = 42 × 3/84 × 3 = 126/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
15/18 = 15 × 14/18 × 14 = 210/252 - Subtract the two like fractions:
126/252 - 210/252 = 126 - 210/252 = -84/252 - After reducing the fraction, the answer is -1/3
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