In the following lever system, what is the counter-clockwise torque? 6 nm 300 nm 1,200 nm 1,800 nm

The answer is: 300 N.m

Torque is equal to the product between the applied force and the distance from the pivot  (where the lever is supported), we are given a lever system with 2 applied forces at different distances from the pivot, and we are asked to find what is the counter-clockwise torque, so:

The counter-clockwise torque is located at the left end of the lever, so:

So, the counter-clockwise torque is equal to 300 N.m.

Also, we can calculate the clockwise torque:

Have a nice day!

the correct answer is b