Answers

Subtract 30/21 from 84/90

1^st number: 84/90, 2^nd number: 1 9/21

84/90 - 30/21 is -52/105.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 21 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   84/90 = 84 × 7/90 × 7 = 588/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   30/21 = 30 × 30/21 × 30 = 900/630
4. Subtract the two like fractions:
   588/630 - 900/630 = 588 - 900/630 = -312/630
5. After reducing the fraction, the answer is -52/105

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