SOLUTION: It takes an avarege of 70 minutes with standard deviation of 10 minutes to assemble a particular microcomputer. Assume that assembly time is normally distributed. What is the prob

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Question 770754: It takes an avarege of 70 minutes with standard deviation of 10 minutes to assemble a particular microcomputer. Assume that assembly time is normally distributed.
What is the probability that a given microcomputer will:
1. take between 70 and 80 minutes to be assembled?
2. will be assembled within 62 minutes?
3. take between 56 and 72 minutes to be assembled?
Answer by Jc0110(165) About Me  (Show Source):
You can put this solution on YOUR website!
1. P(70≤X≤80)≤
=P(%2870-70%29%2F10≤Z≤%2880-70%29%2F10))
=P(0≤Z≤1)
=0.5-0.1587
=0.3413
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2. P(X≤62)
=P(Z≤%2862-70%29%2F10)
=P(Z≤-0.8)
=0.2119
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3. P(56≤X≤72)
=P(%2856-70%29%2F10≤Z≤%2872-70%29%2F10))
=P(-1.4≤Z≤0.2)
=1-0.0808-0.4207
=0.4985