Answers

Subtract 21/81 from 27/80

27/80 - 21/81 is 169/2160.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 81 is 6480
   
   Next, find the equivalent fraction of both fractional numbers with denominator 6480
2. For the 1st fraction, since 80 × 81 = 6480,
   27/80 = 27 × 81/80 × 81 = 2187/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   21/81 = 21 × 80/81 × 80 = 1680/6480
4. Subtract the two like fractions:
   2187/6480 - 1680/6480 = 2187 - 1680/6480 = 507/6480
5. After reducing the fraction, the answer is 169/2160

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