Subtract 4/81 from 21/36
21/36 - 4/81 is 173/324.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 36 × 9 = 324,
21/36 = 21 × 9/36 × 9 = 189/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
4/81 = 4 × 4/81 × 4 = 16/324 - Subtract the two like fractions:
189/324 - 16/324 = 189 - 16/324 = 173/324
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