Answer:
[tex]W=970\ N[/tex]
Explanation:
When two people carry a weight placing it on a very light board then we neglect the weight of the board and the board acts like a beam with two mass placed over it and two end point supports are here provided by men.
Then balancing the forces in the vertical direction, weight of the motor is:
[tex]W=350+620[/tex]
[tex]W=970\ N[/tex]
These men are able to carry the motor in equilibrium condition because they have placed the motor (considering it a point mass) at a position such that the moment due to the lifting forces are equal and opposite.