Answers

Subtract 21/15 from 8/21

1^st number: 8/21, 2^nd number: 1 6/15

8/21 - 21/15 is -107/105.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 15 is 105
   
   Next, find the equivalent fraction of both fractional numbers with denominator 105
2. For the 1st fraction, since 21 × 5 = 105,
   8/21 = 8 × 5/21 × 5 = 40/105
3. Likewise, for the 2nd fraction, since 15 × 7 = 105,
   21/15 = 21 × 7/15 × 7 = 147/105
4. Subtract the two like fractions:
   40/105 - 147/105 = 40 - 147/105 = -107/105

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