Answers

Subtract 3/21 from 84/72

1^st number: 1 12/72, 2^nd number: 3/21

84/72 - 3/21 is 43/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 21 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 72 × 7 = 504,
   84/72 = 84 × 7/72 × 7 = 588/504
3. Likewise, for the 2nd fraction, since 21 × 24 = 504,
   3/21 = 3 × 24/21 × 24 = 72/504
4. Subtract the two like fractions:
   588/504 - 72/504 = 588 - 72/504 = 516/504
5. After reducing the fraction, the answer is 43/42
6. In mixed form: 11/42

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