Subtract 81/72 from 7/18
1st number: 7/18, 2nd number: 1 9/72
7/18 - 81/72 is -53/72.
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,
81/72 = 81 × 1/72 × 1 = 81/72 - Subtract the two like fractions:
28/72 - 81/72 = 28 - 81/72 = -53/72
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