Subtract 9/18 from 5/42
5/42 - 9/18 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
5/42 = 5 × 3/42 × 3 = 15/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
9/18 = 9 × 7/18 × 7 = 63/126 - Subtract the two like fractions:
15/126 - 63/126 = 15 - 63/126 = -48/126 - After reducing the fraction, the answer is -8/21
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