Answers

Add 84/8 and 42/21

1^st number: 10 4/8, 2^nd number: 2 0/21

84/8 + 42/21 is 25/2.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 8 and 21 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 8 × 21 = 168,
   84/8 = 84 × 21/8 × 21 = 1764/168
3. Likewise, for the 2nd fraction, since 21 × 8 = 168,
   42/21 = 42 × 8/21 × 8 = 336/168
4. Add the two like fractions:
   1764/168 + 336/168 = 1764 + 336/168 = 2100/168
5. 2100/168 simplified gives 25/2
6. So, 84/8 + 42/21 = 25/2
   In mixed form: 121/2

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