We need to define the variables,
So,
Therefore, the probability that the repair time is more than 4 horus can be calculate as,
The probability that the repair time is more than 4 hours is 0.136
b) The probability that repair time is at least 12 hours given that the repair time is more than 7 hoirs is calculated as,
The probability that repair time is at least 12 hours given that the repair time is more than 7 hours is 0.63
Answer:
86 mm
Explanation:
From the attached thermal circuit diagram, equation for i-nodes will be
Equation 1
Similarly, the equation for outer node “o” will be
Equation 2
The conventive thermal resistance in i-node will be
Equation 3
The conventive hermal resistance per unit area is
Equation 4
The conductive thermal resistance per unit area is
Equation 5
Since is given as 100,
is 40
is 300
is 25
Substituting the values in equations 3,4 and 5 into equations 1 and 2 we obtain
Equation 6
Equation 7
From equation 6 we can substitute wherever there’s with 3000L+40 as seen in equation 7 hence we obtain
The above can be simplified to be
-3000L=1.665-260
Therefore, insulation thickness is 86mm
