Answers

Add 81/70 and 28/40

1^st number: 1 11/70, 2^nd number: 28/40

81/70 + 28/40 is 13/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 40 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 70 × 4 = 280,
   81/70 = 81 × 4/70 × 4 = 324/280
3. Likewise, for the 2nd fraction, since 40 × 7 = 280,
   28/40 = 28 × 7/40 × 7 = 196/280
4. Add the two like fractions:
   324/280 + 196/280 = 324 + 196/280 = 520/280
5. 520/280 simplified gives 13/7
6. So, 81/70 + 28/40 = 13/7
   In mixed form: 16/7

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