Subtract 7/18 from 20/72
20/72 - 7/18 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
20/72 = 20 × 1/72 × 1 = 20/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
7/18 = 7 × 4/18 × 4 = 28/72 - Subtract the two like fractions:
20/72 - 28/72 = 20 - 28/72 = -8/72 - After reducing the fraction, the answer is -1/9
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