Subtract 30/4 from 21/81
1st number: 21/81, 2nd number: 7 2/4
21/81 - 30/4 is -391/54.
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,
21/81 = 21 × 4/81 × 4 = 84/324 - Likewise, for the 2nd fraction, since 4 × 81 = 324,
30/4 = 30 × 81/4 × 81 = 2430/324 - Subtract the two like fractions:
84/324 - 2430/324 = 84 - 2430/324 = -2346/324 - After reducing the fraction, the answer is -391/54
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