Note the values of a and b are not given in problem In the f

Note: the values of a and b are not given in problem

In the figure above, in order for the system to not move, what value would the 12 N force need to be changed to? 1.19 N 2.24.5 N 3.47. 5N 4.12N

Taking moment about O and equating to zero.

10*b + 9*b -12*a=0

19*b=12*a

since a<b

12 should be replaced with no. greater than 19 for equation to balance.

therefore answer is either 24.5 or 47.5

exact answer can be calculated only when relation between a and b be known.