Three people pull simultaneously on a stubborn donkey. Jack pulls eastward with a force of 79.5 N, Jill pulls with 67.3 N in the northeast direction, and Jane pulls to the southeast with 155 N.

Poor donkey! :-(

To find the direction and magnitude of the resultant force, we can break down the forces into horizontal and vertical components.

1. Start by drawing a diagram. Represent the east direction as positive x and the north direction as positive y. Draw a vector for each person's force, indicating the direction and magnitude.

2. Break down each force into horizontal (x) and vertical (y) components. Use trigonometry to determine the values of the components.
- Jack's force: The force is entirely in the east direction, so the x-component is 79.5 N and the y-component is 0 N.
- Jill's force: The force is in the northeast direction, which is a 45-degree angle with the x-axis. The magnitude of the x-component can be found using the cosine function: cos(45°) = √2/2. Multiply this value by the magnitude of the force (67.3 N) to get the x-component. The y-component can be found using the sine function: sin(45°) = √2/2. Multiply this value by the magnitude of the force (67.3 N) to get the y-component.
- Jane's force: The force is in the southeast direction, which is a 45-degree angle with the x-axis. The magnitude of the x-component can be found using the cosine function: cos(45°) = √2/2. Multiply this value by the magnitude of the force (155 N) to get the x-component. The y-component can be found using the sine function: sin(45°) = √2/2. Multiply this value by the magnitude of the force (155 N) to get the y-component.

3. Add up the x-components and the y-components separately.
- Sum of x-components: 79.5 N + (√2/2 * 67.3 N) + (√2/2 * 155 N).
- Sum of y-components: 0 N + (√2/2 * 67.3 N) - (√2/2 * 155 N).

4. Calculate the magnitude of the resultant force using the formula: √(sum of x-components)^2 + (sum of y-components)^2.

5. Calculate the direction of the resultant force using the inverse tangent (arctan) function:
- Direction (in degrees) = arctan((sum of y-components) / (sum of x-components)).

6. Convert the direction to a more commonly used compass direction (e.g., north, south, east, west).

By following these steps, you can find the magnitude and direction of the resultant force.