Answers

Subtract 21/30 from 10/21

10/21 - 21/30 is -47/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 30 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 21 × 10 = 210,
   10/21 = 10 × 10/21 × 10 = 100/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   21/30 = 21 × 7/30 × 7 = 147/210
4. Subtract the two like fractions:
   100/210 - 147/210 = 100 - 147/210 = -47/210

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