Answers

Add 18/21 and 81/40

1^st number: 18/21, 2^nd number: 2 1/40

18/21 + 81/40 is 807/280.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 21 × 40 = 840,
   18/21 = 18 × 40/21 × 40 = 720/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   81/40 = 81 × 21/40 × 21 = 1701/840
4. Add the two like fractions:
   720/840 + 1701/840 = 720 + 1701/840 = 2421/840
5. 2421/840 simplified gives 807/280
6. So, 18/21 + 81/40 = 807/280
   In mixed form: 2247/280

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