In: Statistics and Probability
La duración de una bombilla sigue una distribución exponencial con una vida promedio de 800 horas.
a) Cuál es la probabilidad de que falle después de 900 horas.
b) Si la bombilla ha trabajado durante 750 horas sin fallar cual es la probabilidad de que falle en las próximas 100 horas.
The converted question in English:
The life of a light bulb follows an exponential distribution with an average life of 800 hours. a) What is the probability that it will fail after 900 hours. b) If the bulb has worked for 750 hours without failing, what is the probability that it will fail in the next 100 hours.
a)
The provided mean is β=800.
We need to compute Pr(X≥900). Therefore, the following is obtained:
which completes the calculation.
b)
The exponential distribution is memoryless i.e. the past has no effect on any future probability:
Hence
Therefore, the following is obtained:
which completes the calculation.
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