Answers

Subtract 5/81 from 21/80

21/80 - 5/81 is 1301/6480.

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,
   21/80 = 21 × 81/80 × 81 = 1701/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   5/81 = 5 × 80/81 × 80 = 400/6480
4. Subtract the two like fractions:
   1701/6480 - 400/6480 = 1701 - 400/6480 = 1301/6480

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