Subtract 81/8 from 20/18
1st number: 1 2/18, 2nd number: 10 1/8
20/18 - 81/8 is -649/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
20/18 = 20 × 4/18 × 4 = 80/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
81/8 = 81 × 9/8 × 9 = 729/72 - Subtract the two like fractions:
80/72 - 729/72 = 80 - 729/72 = -649/72
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