Answer:
a) The probability that none of the lines experiences a surface finish problem in 41 hours of operation is 0.0498.
b)The probability that all three lines experience a surface finish problem between 24 and 41 hours of operation is 0.0346.
Step-by-step explanation:
[tex]Mean = \frac{1}{\lambda} = 41\\P(X\leq x)= 1-e^{-\lambda x}[/tex]
[tex]P(X>x)= e^{-\lambda x}[/tex]
a)
[tex]P(x> 41, y>41, Z>41) = (P(X>41))^{3}\\\\P(X>41)=e^{^{-\frac{41}{41}}}=e^{-1}[/tex]
[tex]P(x> 41, y>41, Z>41) = \left (e^{-1} \right )^{3}\\\\P(x> 41, y>41, Z>41) = e^{-3} = 0.0498.[/tex]
b)
[tex]\lambda =\frac{24}{41}\\P(X=1)=e^{-\lambda }\cdot \lambda =\left ( e^{-0.585} \right )\left ( 0.585 \right )\\P(X=1)=0.326[/tex]
For 3 where, P(X=1, Y==1, Z=1)
[tex]= (0.326)^{3} \\\\= 0.0346[/tex]