Question
In: Statistics and Probability
A cell phone supplier claims that the operating time before failure of its devices (denoted X...
A cell phone supplier claims that the operating time before failure of its devices (denoted X and expressed in years) follows an exponential law of theta parameter. We know that 60% of devices operate without failure for at least 2 years.
a) What is the average lifespan of the devices?
b) What is the time t such that 50% of the devices operate less than t years?
c) If you have had a device from this manufacturer for 2 years, what is the probability that it will still work at least 3 more years?
Solutions
Expert Solution
Answer:
Given that:
A cell phone supplier claims that the operating time before failure of its devices (denoted X and expressed in years) follows an exponential law of theta parameter. We know that 60% of devices operate without failure for at least 2 years.
a) What is the average lifespan of the devices?
Average life span = 
b) What is the time t such that 50% of the devices operate less than t years?
c) If you have had a device from this manufacturer for 2 years, what is the probability that it will still work at least 3 more years?
orchestra answered 1 year agoRelated Solutions
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