If the valve can be opened with a couple moment of 25 N•m, determine the required magnitude of each couple force which must be applied to the wheel.

Image from: Hibbeler, R. C., S. C. Fan, Kai Beng. Yap, and Peter Schiavone. Statics: Mechanics for Engineers. Singapore: Pearson, 2013.
Solution:
As the required couple moment is 25 N•m, we can write an equation to figure out the force required to create such a moment.
25=F(0.15+0.15)
(note we converted mm to m)
F=83.3 N
We assumed clockwise moment to be positive, however, if the opposite was assumed, then force F would also be negative, leading to the same answer.