Answers

Subtract 21/30 from 8/15

8/15 - 21/30 is -1/6.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 30 is 30
   
   Next, find the equivalent fraction of both fractional numbers with denominator 30
2. For the 1st fraction, since 15 × 2 = 30,
   8/15 = 8 × 2/15 × 2 = 16/30
3. Likewise, for the 2nd fraction, since 30 × 1 = 30,
   21/30 = 21 × 1/30 × 1 = 21/30
4. Subtract the two like fractions:
   16/30 - 21/30 = 16 - 21/30 = -5/30
5. After reducing the fraction, the answer is -1/6

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