2.  1) A table has a weight of 55 lb with its center of gravity at . A crate with a weight of  is put in the position shown, and the center of gravity is .  To keep the table from tipping over, what is the largest weight of the crate?

     2) After the measurement of several crates,  is known to follow a normal distribution , and due to manufacturing imprecision,  also follows a normal distribution .  What is the probability that the table will tip over?  and  are independently distributed.

Solution

1)

We suppose; this is the minimum vertical reaction force required to keep the table from tipping over.  . From above equation,              

                                                                                                                   Ans.

 

2) 

We know  and , so we can find and

If the table will tip over, . The probability is

                                                             Ans.