Answers

Add 21/42 and 45/40

1^st number: 21/42, 2^nd number: 1 5/40

21/42 + 45/40 is 13/8.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   21/42 = 21 × 20/42 × 20 = 420/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   45/40 = 45 × 21/40 × 21 = 945/840
4. Add the two like fractions:
   420/840 + 945/840 = 420 + 945/840 = 1365/840
5. 1365/840 simplified gives 13/8
6. So, 21/42 + 45/40 = 13/8
   In mixed form: 15/8

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