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2 years ago

14

The newest CREE led has a life expectancy of mu = 50000 hours and its life probability density function is given by: f(t) = [e^(

-t/mu)]/[mu] if t greater or = 0 and f(t) = 0 if t < 0. Calculate the chance that a led will last at least tau = 100000.

1 answer:

ad-work [718]2 years ago

3 0

Answer:

change that a lead is 0.13533

Explanation:

µ = 50000

f(t) = [e^(-t/µ )]/[µ if t ≥ 0

f(t) = 0 if t < 0

τ = 100000

to find out

the chance that a led will last

solution

we know function is f(t) = [e^(-τ/µ)]/[µ]

τ = 100000

so we can say that probability (τ ≥ 100000 ) that is

= 1 - Probability ( τ ≤ 100000 )

that is function of F so

= 1 - f ( 100000 )

that will be

= 1 - ( 1 - [e^(-τ/µ)]/[µ] )

put all value here τ = 100000 and µ = 50000

= 1 - ( 1 - [e^(-100000/50000)] )

= 1 - 1 - [e^(-100000/50000)]

= 0.13533

so that change that a lead is 0.13533

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