Diameter- The line that goes through the circle is the diameter to find the diameter take the radius and multiply it by two
Circumference- Take the radius divide by two and multiply by pi which is 3.14
P(most favorable outcome) = 1 -(0.03 +0.16 -0.01) = 0.82
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"repair fails" includes the "infection and failure" case, as does "infection". By adding the probability of "repair fails" and "infection", we count the "infection and failure" case twice. So, we have to subtract the probability of "infection and failure" from the sum of "repaire fails" and "infection" in order to count each bad outcome only once.
The probability of a good outcome is the complement of the probability of a bad outcome.
A = P + I
2a = a + PTR/100
2a = a + 5aT/100
2a = a(1+T/20)
2=1+T/20
T=20 yrs
