17. A
frictionless pulley system, which lifts a box, is shown in the figure. The
weight of the box follows a normal distribution 
. The coefficient of friction between the box and
the surface 
is 0.25. The
resistances of the two cables follow distributions 
and 
. Determine
the probabilities of failure of the cables. 
are
independently distributed.
Solution
The
probabilities of failure of cable 1 and cable 2 are 
and 
.