moment effect

Problem 246
Determine the resultant moment about point A of the system of forces shown in Fig. P-246. Each square is 1 ft on a side.
 

Problem 227
Two forces P and Q pass through a point A which is 4 m to the right of and 3 m above a moment center O. Force P is 890 N directed up to the right at 30° with the horizontal and force Q is 445 N directed up to the left at 60° with the horizontal. Determine the moment of the resultant of these two forces with respect to O.