Answers

Subtract 8/21 from 15/30

15/30 - 8/21 is 5/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 21 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 30 × 7 = 210,
   15/30 = 15 × 7/30 × 7 = 105/210
3. Likewise, for the 2nd fraction, since 21 × 10 = 210,
   8/21 = 8 × 10/21 × 10 = 80/210
4. Subtract the two like fractions:
   105/210 - 80/210 = 105 - 80/210 = 25/210
5. After reducing the fraction, the answer is 5/42

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