Subtract 18/36 from 5/42
5/42 - 18/36 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 42 × 6 = 252,
5/42 = 5 × 6/42 × 6 = 30/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
18/36 = 18 × 7/36 × 7 = 126/252 - Subtract the two like fractions:
30/252 - 126/252 = 30 - 126/252 = -96/252 - After reducing the fraction, the answer is -8/21
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