The lifetime of a microprocessor is exponentially distributed with a variance of 4,000,000 hours.
a. What proportion of microprocessors will function for less than 5,000 hours?
b. A microprocessor has been functioning for 1,000 hours. What is the probability that it will
function for a total of at least 6,000 hours?
Ans:
a)
mean=sqrt(4000000)=2000
P(T<=5000)=1-exp(-5000/2000)=0.9179
b)
P(T>=6000/T>=1000)=P(T>=5000)
=exp(-5000/2000)=0.0821
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