Answers

Add 21/42 and 90/15

1^st number: 21/42, 2^nd number: 6 0/15

21/42 + 90/15 is 13/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 15 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 42 × 5 = 210,
   21/42 = 21 × 5/42 × 5 = 105/210
3. Likewise, for the 2nd fraction, since 15 × 14 = 210,
   90/15 = 90 × 14/15 × 14 = 1260/210
4. Add the two like fractions:
   105/210 + 1260/210 = 105 + 1260/210 = 1365/210
5. 1365/210 simplified gives 13/2
6. So, 21/42 + 90/15 = 13/2
   In mixed form: 61/2

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