Answers

Subtract 80/7 from 90/21

1^st number: 4 6/21, 2^nd number: 11 3/7

90/21 - 80/7 is -50/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 7 is 21
   
   Next, find the equivalent fraction of both fractional numbers with denominator 21
2. For the 1st fraction, since 21 × 1 = 21,
   90/21 = 90 × 1/21 × 1 = 90/21
3. Likewise, for the 2nd fraction, since 7 × 3 = 21,
   80/7 = 80 × 3/7 × 3 = 240/21
4. Subtract the two like fractions:
   90/21 - 240/21 = 90 - 240/21 = -150/21
5. After reducing the fraction, the answer is -50/7

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