Answers

Subtract 90/80 from 30/84

1^st number: 30/84, 2^nd number: 1 10/80

30/84 - 90/80 is -43/56.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 84 × 20 = 1680,
   30/84 = 30 × 20/84 × 20 = 600/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   90/80 = 90 × 21/80 × 21 = 1890/1680
4. Subtract the two like fractions:
   600/1680 - 1890/1680 = 600 - 1890/1680 = -1290/1680
5. After reducing the fraction, the answer is -43/56

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