Subtract 30/42 from 6/18
6/18 - 30/42 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
6/18 = 6 × 7/18 × 7 = 42/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
30/42 = 30 × 3/42 × 3 = 90/126 - Subtract the two like fractions:
42/126 - 90/126 = 42 - 90/126 = -48/126 - After reducing the fraction, the answer is -8/21
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