Answers

Subtract 21/81 from 15/25

15/25 - 21/81 is 46/135.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 25 and 81 is 2025
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2025
2. For the 1st fraction, since 25 × 81 = 2025,
   15/25 = 15 × 81/25 × 81 = 1215/2025
3. Likewise, for the 2nd fraction, since 81 × 25 = 2025,
   21/81 = 21 × 25/81 × 25 = 525/2025
4. Subtract the two like fractions:
   1215/2025 - 525/2025 = 1215 - 525/2025 = 690/2025
5. After reducing the fraction, the answer is 46/135

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