Answers

Add 8/28 and 81/40

1^st number: 8/28, 2^nd number: 2 1/40

8/28 + 81/40 is 647/280.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 28 and 40 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 28 × 10 = 280,
   8/28 = 8 × 10/28 × 10 = 80/280
3. Likewise, for the 2nd fraction, since 40 × 7 = 280,
   81/40 = 81 × 7/40 × 7 = 567/280
4. Add the two like fractions:
   80/280 + 567/280 = 80 + 567/280 = 647/280
5. So, 8/28 + 81/40 = 647/280
   In mixed form: 287/280

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