Answers

Add 21/7 and 81/80

1^st number: 3 0/7, 2^nd number: 1 1/80

21/7 + 81/80 is 321/80.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 7 and 80 is 560
   
   Next, find the equivalent fraction of both fractional numbers with denominator 560
2. For the 1st fraction, since 7 × 80 = 560,
   21/7 = 21 × 80/7 × 80 = 1680/560
3. Likewise, for the 2nd fraction, since 80 × 7 = 560,
   81/80 = 81 × 7/80 × 7 = 567/560
4. Add the two like fractions:
   1680/560 + 567/560 = 1680 + 567/560 = 2247/560
5. 2247/560 simplified gives 321/80
6. So, 21/7 + 81/80 = 321/80
   In mixed form: 41/80

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