7) ¿En cuál(es) de las sigulentes afirmaciones, la probabilidad de ocurrencia del suces mencionado, es siempre igual a la probabilidad de no ocurrencia del mismo suceso? I) Que salga sello en el lanzamiento de una moneda. II) Que salga un número impar, al lanzar un dado común III) Que salga una ficha verde al extraerla al azar, desde una urna que contiene sólo fiche rojas y verdes, todas del mismo tipo. A) Sólo I B) Sólo III C) Sólo Iy II D) Sólo Iy III E) I, II y III

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.

Michelle puts 7 red marbles and 5 blue marbles into a bag. If two marbles are chosen at random from the bag, one by one, without replacement, find the probability that two blue marbles are chosen. \( \begin{array}{ll}\text { A } \frac{25}{144} & \text { C } \frac{7}{22} \\ \text { B } \frac{49}{144} & \text { D } \frac{5}{33}\end{array} \)

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?

- 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: \( \begin{array}{l}\text { a) A male under the age of } 30 . \\ \text { b) A female. } \\ \text { c) A male over the age of } 21 . \\ \text { d) A person not older than } 21 . \\ \text { e) A male given that this person is over } 30 \text { years. } \\ \text { f) A female or between } 21 \text { and } 30 . \\ \text { g) A male or a female. }\end{array} \)