Prob-7 The lighting department of a city has installed 2000 electric lamps with an average life of 10,000 h and a standard deviation of 500 h. After what period of lighting hours would we expect 65.54% of the lamps to fail

answer: evaluate the objective function at each vertex to determine which - and -values, if any, maximize or minimize the function. example: find the minimum value and maximum value of the objective function f ( x , y ) = 4 x + 5 y , subject to the following constraints