Answers

Add 21/42 and 25/20

1^st number: 21/42, 2^nd number: 1 5/20

21/42 + 25/20 is 7/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 42 × 10 = 420,
   21/42 = 21 × 10/42 × 10 = 210/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   25/20 = 25 × 21/20 × 21 = 525/420
4. Add the two like fractions:
   210/420 + 525/420 = 210 + 525/420 = 735/420
5. 735/420 simplified gives 7/4
6. So, 21/42 + 25/20 = 7/4
   In mixed form: 13/4

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