9. La probabilidad de obtener dos número: distintos en el lanzamiento de dos dados es

3. In a class of 100 students 75 are boys and 25 are girls. The chance that a boy gets a first class is 0.25 and the probability that a girl first class is 0.21 . find the probability that a student selected at random gets a first class. ( 3 marks )

\( 1 \leftarrow \quad \begin{array}{l}\text { In a race in which five automobiles are entered and there are no ties, in how many ways can the } \\ \text { first three finishers come in? }\end{array} \)

What is the probability of rolling a 1 or a 4 on a number cube labeled 1 through 6 ? B. \( \frac{1}{6} \) D. \( \frac{1}{3} \) E. \( \frac{1}{2} \) E. \( \frac{5}{6} \)

The events that Aaron's team and Betty's team win their next games are \[ \text { of } P(A) \text { and } P(B) \text {. } \] dependent equal product

3. La probabilidad de que cierta clase de componente sobreviva a una prueba de choque es de 0.85. De los siguientes 15 componentes que se prueban calcule la probabilidad de que: a). sobrevivan 10 componentes. \( R=0.04489 \) b). no sobrevivan máximo 2 componentes. \( R=0.6042 \) c) calcule el promedio de componentes que sobreviven. \( R=12.75 \)