physics
posted by shelby .
Three blocks are located on a horizontal table. The coefficient of kinetic friction between the blocks and the table is 0.276. They are connected by a massless cord, as shown in the figure below, and pulled to the right. The masses of the three blocks are = 9.0 kg, = 0.5 kg, and = 5.0 kg. The pulling force is equal to = 82.0 N. What is the tension ?
The three boxes are all connected.

The tension in which cord? You have not provided nor sufficiently described the figure.
I suspect that there is a cord between each block and you want the tension in each one. If so, write a free body equation for each block and solve the three equations in three unkowns. 
blow me.