Subtract 42/81 from 21/4
1st number: 5 1/4, 2nd number: 42/81
21/4 - 42/81 is 511/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 4 × 81 = 324,
21/4 = 21 × 81/4 × 81 = 1701/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
42/81 = 42 × 4/81 × 4 = 168/324 - Subtract the two like fractions:
1701/324 - 168/324 = 1701 - 168/324 = 1533/324 - After reducing the fraction, the answer is 511/108
- In mixed form: 479/108
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