Answers

Subtract 21/18 from 84/20

1^st number: 4 4/20, 2^nd number: 1 3/18

84/20 - 21/18 is 91/30.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 18 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 20 × 9 = 180,
   84/20 = 84 × 9/20 × 9 = 756/180
3. Likewise, for the 2nd fraction, since 18 × 10 = 180,
   21/18 = 21 × 10/18 × 10 = 210/180
4. Subtract the two like fractions:
   756/180 - 210/180 = 756 - 210/180 = 546/180
5. After reducing the fraction, the answer is 91/30
6. In mixed form: 31/30

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