Thank you for the opportunity to help you with your question!

let the force exerted by smaller tug be along x axis direction.

Larger tug exerts 25% more force.

therefore force exerted by larger tug is 1.25x and that by smaller is x.

Force exerted by large tug vertically is 1.25x sin(35).

and that by smaller tug is xsinθ

For ship to travel due east.

the vertical components of two forces need to be zero. x * sinθ+1.25x * sin35=0 sinθ=-1.25*sin35 θ=-sin^-1(1.25*sin35) =-45.8° as larger tug is 35 degrees north of east then the smaller tug must be 45.8 degrees south of east

Please let me know if you need any clarification. I'm always happy to answer your questions.