Answers

Add 15/8 and 21/20

1^st number: 1 7/8, 2^nd number: 1 1/20

15/8 + 21/20 is 117/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 8 and 20 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 8 × 5 = 40,
   15/8 = 15 × 5/8 × 5 = 75/40
3. Likewise, for the 2nd fraction, since 20 × 2 = 40,
   21/20 = 21 × 2/20 × 2 = 42/40
4. Add the two like fractions:
   75/40 + 42/40 = 75 + 42/40 = 117/40
5. So, 15/8 + 21/20 = 117/40
   In mixed form: 237/40

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