Answers

Add 84/42 and 21/80

1^st number: 2 0/42, 2^nd number: 21/80

84/42 + 21/80 is 181/80.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 80 is 1680
2. For the 1st fraction, since 42 × 40 = 1680,
   84/42 = 84 × 40/42 × 40 = 3360/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   21/80 = 21 × 21/80 × 21 = 441/1680
4. Add the two fractions:
   3360/1680 + 441/1680 = 3360 + 441/1680 = 3801/1680
5. 3801/1680 simplified gives 181/80
6. So, 84/42 + 21/80 = 181/80
   In mixed form: 221/80

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