Subtract 81/8 from 20/36
1st number: 20/36, 2nd number: 10 1/8
20/36 - 81/8 is -689/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 36 × 2 = 72,
20/36 = 20 × 2/36 × 2 = 40/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
81/8 = 81 × 9/8 × 9 = 729/72 - Subtract the two like fractions:
40/72 - 729/72 = 40 - 729/72 = -689/72
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