Answers

Subtract 70/90 from 21/98

21/98 - 70/90 is -71/126.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 98 and 90 is 4410
   
   Next, find the equivalent fraction of both fractional numbers with denominator 4410
2. For the 1st fraction, since 98 × 45 = 4410,
   21/98 = 21 × 45/98 × 45 = 945/4410
3. Likewise, for the 2nd fraction, since 90 × 49 = 4410,
   70/90 = 70 × 49/90 × 49 = 3430/4410
4. Subtract the two like fractions:
   945/4410 - 3430/4410 = 945 - 3430/4410 = -2485/4410
5. After reducing the fraction, the answer is -71/126

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