Subtract 7/9 from 18/72
18/72 - 7/9 is -19/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
18/72 = 18 × 1/72 × 1 = 18/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
7/9 = 7 × 8/9 × 8 = 56/72 - Subtract the two like fractions:
18/72 - 56/72 = 18 - 56/72 = -38/72 - After reducing the fraction, the answer is -19/36
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