Subtract 18/72 from 7/42
7/42 - 18/72 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
7/42 = 7 × 12/42 × 12 = 84/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
18/72 = 18 × 7/72 × 7 = 126/504 - Subtract the two like fractions:
84/504 - 126/504 = 84 - 126/504 = -42/504 - After reducing the fraction, the answer is -1/12
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