Skoally

the problem in its entirety is as follows: It can be very expensive to do tests on medical samples, such as blood tests. One method of reducing the expense of such tests is to take the individual samples, take half of each, combine the half samples, and test the composite sample. If the composite sample tests negative for some condition, then all the original samples would have tested negative, and only the one test was needed, saving much money. However, if the composite sample tests positive, then there is no way of knowing which of the original samples would have tested negative and which positive. In that case, all the remaining have to be tested individually, and the test on the composite sample was an extra test, resulting in extra money being spent. On your comment to having the answer to the second question, 10 samples for composite tests, and the probability that any one sample would test positive is .0400. That would be .0410 = 1.0486x10-14 ? Thank you for any guidance you can provide me with!

I am having issues trying to understand how to calculate some probability problems. I understand that I can not be given the answer - I would not want that anyway. I need to know how to get the answer so that I can do the rest of the questions like it. the problem is as follows: 10 composite samples are used to run a composite test, and the probability that any one sample will test positive is 0.0400 what is the probability that the composite sample will test NEGATIVE? What is the Probability that composite sample will test POSITIVE? HOW DO I FIND THE ANSWER, in layman's terms please. I am a stats student right now.