<PRE><B>Question 947572</B>
Let x denote the lifespan of a transistor (in Hour) with the following probabilities : P(X &lt;= 200)= 0.08 and P(X &gt; 600)=0.45
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Note: Draw a normal distribution curve and plot the data
so you can see why the answers are what they are.
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 a)What is the probability that the life is less than or equal to 600 hours?
Ans:: 1-045 = 0.55
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b)What is the probability that the life is greater than 200 hours?
Ans:: 1-0.08 = 0.92
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c) What is P(200&lt; X &lt;= 600)
Ans: 1 - [0.08+0.45] = 1-0.53 = 0.47
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Cheers,
Stan H.
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