Answers

Subtract 21/10 from 20/18

1^st number: 1 2/18, 2^nd number: 2 1/10

20/18 - 21/10 is -89/90.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 10 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 18 × 5 = 90,
   20/18 = 20 × 5/18 × 5 = 100/90
3. Likewise, for the 2nd fraction, since 10 × 9 = 90,
   21/10 = 21 × 9/10 × 9 = 189/90
4. Subtract the two like fractions:
   100/90 - 189/90 = 100 - 189/90 = -89/90

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