Subtract 9/20 from 81/8
1st number: 10 1/8, 2nd number: 9/20
81/8 - 9/20 is 387/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
81/8 = 81 × 5/8 × 5 = 405/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
9/20 = 9 × 2/20 × 2 = 18/40 - Subtract the two like fractions:
405/40 - 18/40 = 405 - 18/40 = 387/40 - In mixed form: 927/40
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