Answers

Subtract 20/21 from 84/30

1^st number: 2 24/30, 2^nd number: 20/21

84/30 - 20/21 is 194/105.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 21 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 30 × 7 = 210,
   84/30 = 84 × 7/30 × 7 = 588/210
3. Likewise, for the 2nd fraction, since 21 × 10 = 210,
   20/21 = 20 × 10/21 × 10 = 200/210
4. Subtract the two like fractions:
   588/210 - 200/210 = 588 - 200/210 = 388/210
5. After reducing the fraction, the answer is 194/105
6. In mixed form: 189/105

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