A box is being pulled with a resultant force of (33i+96j)N by 3 people. Another person starts pulling the box with a force of (100i+pj)N. With all 4 people pulling the box, it moves in the direction of (12i +j). I need to work out the value of p. For this would I add 100 and 33, and then divide by 12 to find the proportions of i. And then with that times it by the 1j to get what j is. E.g. 100+33=133 133/12=11.1 1x11.1=11.1 96+j=11.1 j= -84.9 Or is this totally wrong? Any help at all would be greatly appreciated. Many Thanks!