Answers

Add 45/60 and 80/21

1^st number: 45/60, 2^nd number: 3 17/21

45/60 + 80/21 is 383/84.

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,
   45/60 = 45 × 7/60 × 7 = 315/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   80/21 = 80 × 20/21 × 20 = 1600/420
4. Add the two like fractions:
   315/420 + 1600/420 = 315 + 1600/420 = 1915/420
5. 1915/420 simplified gives 383/84
6. So, 45/60 + 80/21 = 383/84
   In mixed form: 447/84

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