Thirteen cubes of the same size numbered 1 to 13 are placed in a bag. If two cubes are drawn at random from the bag one after the other and not replaced, what is the probability that (i) both cubes are odd numbered, (ii) only one is even numbered.

4. A box contains a total of 100 CDs that were manufactured on two machines. Of them, 60 were manufactured on Machine I. Of the total CDs, 15 are defective. Of the 60 CDs that were manufactured on Machine I, 9 are defective. Let \( D \) be the event that a randomly selected CD is defective, and let A be the event that a randomly selected CD was manufactured on Machine I.

- выпполнить в тетради задание: Бросают две игральные кости. Событие \( A \) «на первой кости выпала тройка». Событие \( B \) - «на второй кости выпала тройка». Найди вероятность события \( A \cup B \). (Ответ округли до тысячных.)

In a group of people on holiday, it is established that there are: - 10 males under the age of 21 - 8 females under the age of 21 - 5 females aged between 21 and 30 - 7 males over the age of 30 Calculate the probability that, if one person is selected at random from the group this person will be: \( \begin{array}{l}\text { a) A male under the age of } 30 . \\ \text { b) A female. } \\ \text { c) A male over the age of } 21 . \\ \text { d) A person not older than } 21 . \\ \text { e) A male given that this person is over } 30 \text { years. } \\ \text { f) A female or between } 21 \text { and } 30 . \\ \text { g) A male or a female. }\end{array} \)

Jim works at an Auto centre and accidentally drops 4 bad spark plugs into a box with 20 good spark plugs. a. If he selects two spark plugs at random from the box without replacement, and the first spark plug selected was a good one, what is the probability that the second spark plug is bad?

A bag contains green balls and red balls only. A ball is taken at random from the bag. The probability of taking a green ball is 0.38 . Write down the probability of taking a a red ball, b a blue ball.