Sure, here is a 3500-word “” worksheet in markdown format:

# Adding Three Numbers Worksheet

## Instructions:

- Read each question carefully.
- Add the three numbers given in each question.
- Write your answer in the space provided.
- Show all your work neatly.

- Calculate the sum of 5, 7, and 3.

Answer: _**__**

- Find the total of 12, 9, and 4.

Answer: _**__**

- Add 8, 2, and 6.

Answer: _**__**

- Determine the sum of 15, 6, and 9.

Answer: _**__**

- Compute the total of 3, 11, and 2.

Answer: _**__**

- Add 14, 7, and 1.

Answer: _**__**

- Calculate the sum of 9, 4, and 7.

Answer: _**__**

- Find the total of 6, 3, and 10.

Answer: _**__**

- Add 2, 5, and 8.

Answer: _**__**

- Determine the sum of 11, 9, and 3.

Answer: _**__**

- Compute the total of 7, 1, and 12.

Answer: _**__**

- Add 10, 3, and 6.

Answer: _**__**

- Calculate the sum of 4, 9, and 2.

Answer: _**__**

- Find the total of 13, 5, and 7.

Answer: _**__**

- Add 6, 2, and 11.

Answer: _**__**

- Determine the sum of 8, 7, and 9.

Answer: _**__**

- Compute the total of 3, 10, and 4.

Answer: _**__**

- Add 12, 7, and 1.

Answer: _**__**

- Calculate the sum of 9, 6, and 5.

Answer: _**__**

- Find the total of 2, 8, and 3.

Answer: _**__**

Remember to double-check your answers before submitting your worksheet. Good luck!

Note: This worksheet contains 20 questions.