Answers

Subtract 90/80 from 50/21

1^st number: 2 8/21, 2^nd number: 1 10/80

50/21 - 90/80 is 211/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 21 × 80 = 1680,
   50/21 = 50 × 80/21 × 80 = 4000/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   90/80 = 90 × 21/80 × 21 = 1890/1680
4. Subtract the two like fractions:
   4000/1680 - 1890/1680 = 4000 - 1890/1680 = 2110/1680
5. After reducing the fraction, the answer is 211/168
6. In mixed form: 143/168

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