Answers

Add 20/15 and 21/18

1^st number: 1 5/15, 2^nd number: 1 3/18

20/15 + 21/18 is 5/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 18 is 90
2. For the 1st fraction, since 15 × 6 = 90,
   20/15 = 20 × 6/15 × 6 = 120/90
3. Likewise, for the 2nd fraction, since 18 × 5 = 90,
   21/18 = 21 × 5/18 × 5 = 105/90
4. Add the two fractions:
   120/90 + 105/90 = 120 + 105/90 = 225/90
5. After reducing the fraction, the answer is 5/2
6. In mixed form: 21/2

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