Step 1 :The problem states that the accuracy of the E.P.T. Pregnancy Test is 99%, or 0.99. This means that the probability of the test correctly identifying a pregnancy is 0.99.
Step 2 :We are asked to find the probability that all 12 tests will be positive. Since each test is independent of the others, we can simply multiply the probabilities together. So, the probability that all 12 tests are positive is \(0.99^{12}\).
Step 3 :We are also asked to find the probability that at least one test will not be positive. This is the complement of the event that all tests are positive. So we can calculate this by subtracting the probability that all tests are positive from 1, which is \(1 - 0.99^{12}\).
Step 4 :Using Python to calculate, we find that the probability that all 12 tests will be positive is approximately 0.886, and the probability that at least one test will not be positive is approximately 0.114.
Step 5 :Final Answer: The probability that all 12 tests will be positive is \(\boxed{0.886}\). The probability that at least one test will not be positive is \(\boxed{0.114}\).