Answers

Add 30/40 and 90/42

1^st number: 30/40, 2^nd number: 2 6/42

30/40 + 90/42 is 81/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 42 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   30/40 = 30 × 21/40 × 21 = 630/840
3. Likewise, for the 2nd fraction, since 42 × 20 = 840,
   90/42 = 90 × 20/42 × 20 = 1800/840
4. Add the two like fractions:
   630/840 + 1800/840 = 630 + 1800/840 = 2430/840
5. 2430/840 simplified gives 81/28
6. So, 30/40 + 90/42 = 81/28
   In mixed form: 225/28

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