Answers

Add 70/18 and 72/80

1^st number: 3 16/18, 2^nd number: 72/80

70/18 + 72/80 is 431/90.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 18 × 40 = 720,
   70/18 = 70 × 40/18 × 40 = 2800/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   72/80 = 72 × 9/80 × 9 = 648/720
4. Add the two like fractions:
   2800/720 + 648/720 = 2800 + 648/720 = 3448/720
5. 3448/720 simplified gives 431/90
6. So, 70/18 + 72/80 = 431/90
   In mixed form: 471/90

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