Answers

Subtract 2/21 from 9/20

9/20 - 2/21 is 149/420.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 21 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 20 × 21 = 420,
   9/20 = 9 × 21/20 × 21 = 189/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   2/21 = 2 × 20/21 × 20 = 40/420
4. Subtract the two like fractions:
   189/420 - 40/420 = 189 - 40/420 = 149/420

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