21 Deux événements \( A \) et \( B \) vérifient \( P(A)=0,45 \), \( P(B)=0,6 \) et \( P(A \cup B)=0,9 \). 1. Calculer \( P(A \cap B) \). 2. En déduire \( P_{B}(A) \) et \( P_{A}(B) \).

3. Combinations and Probabilities: 20 pts. You are tasked with creating a code using the following three conditions: 1. The code must consist of exactly 4 characters. 2. Each character can be one of the following: A, B, C, or D. 3. The code can repeat characters, but the first character must be different from the last character. How many different codes can you create based on these condi- tions? You MUST show all of your steps to receive full credit.

logía, Química, Física y Lenguaje. Si se toma uno de ellos, ¿cuá a probabilidad de que este sea de matemática o de física? \( 1 / 5 \) b) \( 3 / 5 \) c) \( 2 / 5 \mathrm{~d} / 4 / 5 \)

The expected value of betting \( \$ 1 \) on one roulette number is approximately \( -\$ .05 \). What does this mean in practical terms? If many people made this bet over the course of the night, the house would expect to take in approximately a \( 5 \% \) return. If I bet \( \$ 1 \) one time, I would expect to leave the table with approximately 95 cents. I am almost guaranteed to lose this bet I am almost guaranteed to win this bet

4. En un taller mecánico llegan vehículos para una puesta a punto antes de pasar la ITV. Las llegadas siguen un proceso de poisson de promedio de 18 vehículos por hora. Las dimensiones del taller sólo permiten que haya cuatro vehículos y las ordenanzas municipales no permiten esperar en la vía pública. El taller despachó un promedio de 6 vehículos por hora, de acuerdo con una distribución exponencial. Calcule a. Probabilidad de que no haya ningún vehículo en el taller. Calcular las probabilidades. b. Promedio de vehículos en el taller. c. ¿Cuánto tiempo pasa por término medio un vehículo en el taller? d. ¿Cuánto tiempo esperan por término medio los vehículos en cola?

After a particular surgery, patients are placed in an intensive care unit (ICU) until their condition stabilizes. Then they are transferred to a special care ward (SCW), where they remain until they are released from the hospital. In a particular metropolitan area, a study of hospital records produced the following data: each day \( 2 \% \) of the patients in the ICU died, \( 49 \% \) were transferred to the SCW, and the remainder stayed in the ICU. Furthermore, each day \( 3 \% \) of the patients in the SCW developed complications and were returned to the ICU, \( 1 \% \) died while in the SCW, \( 22 \% \) were released from the hospital, and the remainder stayed in the SCW. A) In the long run, what percentage of the patients in the ICU are released from the hospital? \( \square \% \) (Round to two decimal places as needed.)