Answers

Add 81/12 and 42/70

1^st number: 6 9/12, 2^nd number: 42/70

81/12 + 42/70 is 147/20.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 70 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 12 × 35 = 420,
   81/12 = 81 × 35/12 × 35 = 2835/420
3. Likewise, for the 2nd fraction, since 70 × 6 = 420,
   42/70 = 42 × 6/70 × 6 = 252/420
4. Add the two like fractions:
   2835/420 + 252/420 = 2835 + 252/420 = 3087/420
5. 3087/420 simplified gives 147/20
6. So, 81/12 + 42/70 = 147/20
   In mixed form: 77/20

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