Answers

Add 21/15 and 45/56

1^st number: 1 6/15, 2^nd number: 45/56

21/15 + 45/56 is 617/280.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 56 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 15 × 56 = 840,
   21/15 = 21 × 56/15 × 56 = 1176/840
3. Likewise, for the 2nd fraction, since 56 × 15 = 840,
   45/56 = 45 × 15/56 × 15 = 675/840
4. Add the two like fractions:
   1176/840 + 675/840 = 1176 + 675/840 = 1851/840
5. 1851/840 simplified gives 617/280
6. So, 21/15 + 45/56 = 617/280
   In mixed form: 257/280

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