00:01
For this problem, we are told that a computer manufacturer buys 30 % of its chips from supplier a and the rest from supplier b.
00:08
We're then told that 2 % of the chips from supplier a are defective as are 4 % of the chips from supplier b.
00:15
Then we are asked approximately what percentage of the defective chips are from supplier b.
00:20
So this is a problem that we want to address using a tree diagram.
00:24
So our first column here is the supplier.
00:29
So we'll start, then we branch it off.
00:34
So i'll just have p of a, probability that we're getting from supplier a, is going to be, it was 30%, so 0 .3.
00:43
And p of not a is going to equal 0 .7 then.
00:51
Then for the second column, we have is it defective? so, probability for a that it is defective is 0 .02.
01:09
And that it is not defective, it's going to be 0 .98.
01:17
Then, similarly, we branch from that, not a, so the supplier b.
01:22
So, the probability for it to be defective from supplier b is going to be 4%, so 0 .04.
01:32
And probability that it is not defective, so p of d not, is going to be 0 .96.
01:42
6.
01:44
So we are asked about approximately what percentage of the defective chips are from supplier b...