Subtract 42/72 from 7/18
7/18 - 42/72 is -7/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
7/18 = 7 × 4/18 × 4 = 28/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
42/72 = 42 × 1/72 × 1 = 42/72 - Subtract the two like fractions:
28/72 - 42/72 = 28 - 42/72 = -14/72 - After reducing the fraction, the answer is -7/36
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