Subtract 5/4 from 42/81
1st number: 42/81, 2nd number: 1 1/4
42/81 - 5/4 is -79/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 4 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
42/81 = 42 × 4/81 × 4 = 168/324 - Likewise, for the 2nd fraction, since 4 × 81 = 324,
5/4 = 5 × 81/4 × 81 = 405/324 - Subtract the two like fractions:
168/324 - 405/324 = 168 - 405/324 = -237/324 - After reducing the fraction, the answer is -79/108
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