Answers

Add 21/42 and 90/40

1^st number: 21/42, 2^nd number: 2 10/40

21/42 + 90/40 is 11/4.

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,
   90/40 = 90 × 21/40 × 21 = 1890/840
4. Add the two like fractions:
   420/840 + 1890/840 = 420 + 1890/840 = 2310/840
5. 2310/840 simplified gives 11/4
6. So, 21/42 + 90/40 = 11/4
   In mixed form: 23/4

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