Answers

Add 80/60 and 15/21

1^st number: 1 20/60, 2^nd number: 15/21

80/60 + 15/21 is 43/21.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 21 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 60 × 7 = 420,
   80/60 = 80 × 7/60 × 7 = 560/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   15/21 = 15 × 20/21 × 20 = 300/420
4. Add the two like fractions:
   560/420 + 300/420 = 560 + 300/420 = 860/420
5. 860/420 simplified gives 43/21
6. So, 80/60 + 15/21 = 43/21
   In mixed form: 21/21

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