**Solution using old fashioned descriptive geometry and 2d sketches: ***This is the method used to generate the challenge.*

Create a sketch for the 3 smaller spheres on plane XY. Centerpoints for these spheres are at points A, B, and C. Create circles D and E with a diameter equal to the larger sphere. Circle D is tangent to circles A and B and circle E tangent to circles B and C. Create semicircles A and B along with their centerline AB. It is important that Line BC is perpendicular to the Y axis and point E is constrained to the Y axis. Revolve semicircles A and B to create the first two spheres.

Create a plane perpendicular to line AB through point D. Create a sketch on this plane and project line AB and point D onto it. Revolve a circle with centerpoint B through point D. This circle (shown in yellow) becomes the path for the larger sphere as it rolls around spheres A and B.

Create a sketch on the YZ plane and project the circle created in the previous sketch onto it. (That is the narrow yellow ellipse in the following picture.) Project line BC and point E onto the sketch. Revolve a circle with centerpoint B through point E. This circle (shown in cyan) becomes the possible path for the larger sphere as it rolls around spheres B and C. Point F is the intersection of the two paths. Create semicircle F for the larger sphere. The axis inclination is unimportant. Note that there are 4 possible intersection points between the two paths. Logic will dictate which point is the correct choice.

Revolve semicircle F to create the larger sphere.

Create another sketch on plane XY and project circle C from the first sketch. draw semicircle C with its axis.

Revolve semicircle C to create the final sphere. The end result requires 5 features including a layout sketch and a workplane.

And then create the drawing views to check the location