Answers

Add 21/12 and 54/70

1^st number: 1 9/12, 2^nd number: 54/70

21/12 + 54/70 is 353/140.

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,
   21/12 = 21 × 35/12 × 35 = 735/420
3. Likewise, for the 2nd fraction, since 70 × 6 = 420,
   54/70 = 54 × 6/70 × 6 = 324/420
4. Add the two like fractions:
   735/420 + 324/420 = 735 + 324/420 = 1059/420
5. 1059/420 simplified gives 353/140
6. So, 21/12 + 54/70 = 353/140
   In mixed form: 273/140

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