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In this problem, it is said that a purchaser of transistors buys them in lots of 20.
00:05
It is his policy to randomly inspect four components from a lot and to accept the lot only if all four are non -defective.
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If each component in a lot is independently defective with probability 0 .1, then one proportion of lots is rejected.
00:19
So, to find the proportion of lots that are rejected, let us find the probability of a lot being rejected.
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That will give us our answer.
00:27
And the probability of a lot being rejected will be one minus the probability of the lot being accepted.
00:34
This is because the lot being accepted and the lot being rejected are both complementary events.
00:41
So we have one minus probability of the lot being accepted and the lot is accepted only if all four are non -defective.
00:48
Now, the probability that a component is defective is 0 .1.
00:54
So the probability that it is not defective will be one, minus 0 .1.
00:59
And we need all 4 to be non -defective...