Answers

Subtract 84/80 from 28/21

1^st number: 1 7/21, 2^nd number: 1 4/80

28/21 - 84/80 is 17/60.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 21 × 80 = 1680,
   28/21 = 28 × 80/21 × 80 = 2240/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   84/80 = 84 × 21/80 × 21 = 1764/1680
4. Subtract the two like fractions:
   2240/1680 - 1764/1680 = 2240 - 1764/1680 = 476/1680
5. After reducing the fraction, the answer is 17/60

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