Answers

Subtract 98/90 from 21/28

1^st number: 21/28, 2^nd number: 1 8/90

21/28 - 98/90 is -61/180.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 28 and 90 is 1260
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1260
2. For the 1st fraction, since 28 × 45 = 1260,
   21/28 = 21 × 45/28 × 45 = 945/1260
3. Likewise, for the 2nd fraction, since 90 × 14 = 1260,
   98/90 = 98 × 14/90 × 14 = 1372/1260
4. Subtract the two like fractions:
   945/1260 - 1372/1260 = 945 - 1372/1260 = -427/1260
5. After reducing the fraction, the answer is -61/180

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