bac-s-maths 2024 Q1

bac-s-maths · France · bac-spe-maths__polynesie_j2 4 marks Conditional Probability Total Probability via Tree Diagram (Two-Stage Partition)
A survey conducted in France provides the following information:
  • $60\%$ of people over 15 years old intend to watch the Paris 2024 Olympic and Paralympic Games (OPG) on television;
  • among those who intend to watch the OPG, 8 out of 9 people declare that they regularly practice a sport.
A person over 15 years old is chosen at random. The following events are considered:
  • $J$: ``the person intends to watch the Paris 2024 OPG on television'';
  • $S$: ``the chosen person declares that they regularly practice a sport''.
We denote by $\bar{J}$ and $\bar{S}$ their complementary events.
In questions 1. and 2., probabilities will be given in the form of an irreducible fraction.
  1. Demonstrate that the probability that the chosen person intends to watch the Paris 2024 OPG on television and declares that they regularly practice a sport is $\frac{8}{15}$. A weighted tree diagram may be used.
    According to this survey, two out of three people over 15 years old declare that they regularly practice a sport.
  2. [2.] a. Calculate the probability that the chosen person does not intend to watch the Paris 2024 OPG on television and declares that they regularly practice a sport. b. Deduce the probability of $S$ given $\bar{J}$ denoted $P_{\bar{J}}(S)$.
    In the rest of the exercise, results will be rounded to the nearest thousandth.
  3. [3.] As part of a promotional operation, 30 people over 15 years old are chosen at random. This choice is treated as sampling with replacement. Let $X$ be the random variable that gives the number of people declaring that they regularly practice a sport among the 30 people. a. Determine the nature and parameters of the probability distribution followed by $X$. b. Calculate the probability that exactly 16 people declare that they regularly practice a sport among the 30 people. c. The French judo federation wishes to offer a ticket for the final of the mixed team judo event at the Arena Champ-de-Mars for each person declaring that they regularly practice a sport among these 30 people. The price of a ticket is $380\,€$ and a budget of 10000 euros is available for this operation. What is the probability that this budget is insufficient?
A survey conducted in France provides the following information:
\begin{itemize}
  \item $60\%$ of people over 15 years old intend to watch the Paris 2024 Olympic and Paralympic Games (OPG) on television;
  \item among those who intend to watch the OPG, 8 out of 9 people declare that they regularly practice a sport.
\end{itemize}
A person over 15 years old is chosen at random. The following events are considered:
\begin{itemize}
  \item $J$: ``the person intends to watch the Paris 2024 OPG on television'';
  \item $S$: ``the chosen person declares that they regularly practice a sport''.
\end{itemize}
We denote by $\bar{J}$ and $\bar{S}$ their complementary events.

In questions 1. and 2., probabilities will be given in the form of an irreducible fraction.

\begin{enumerate}
  \item Demonstrate that the probability that the chosen person intends to watch the Paris 2024 OPG on television and declares that they regularly practice a sport is $\frac{8}{15}$. A weighted tree diagram may be used.

  According to this survey, two out of three people over 15 years old declare that they regularly practice a sport.

  \item[2.] a. Calculate the probability that the chosen person does not intend to watch the Paris 2024 OPG on television and declares that they regularly practice a sport.\\
  b. Deduce the probability of $S$ given $\bar{J}$ denoted $P_{\bar{J}}(S)$.

  In the rest of the exercise, results will be rounded to the nearest thousandth.

  \item[3.] As part of a promotional operation, 30 people over 15 years old are chosen at random. This choice is treated as sampling with replacement. Let $X$ be the random variable that gives the number of people declaring that they regularly practice a sport among the 30 people.\\
  a. Determine the nature and parameters of the probability distribution followed by $X$.\\
  b. Calculate the probability that exactly 16 people declare that they regularly practice a sport among the 30 people.\\
  c. The French judo federation wishes to offer a ticket for the final of the mixed team judo event at the Arena Champ-de-Mars for each person declaring that they regularly practice a sport among these 30 people. The price of a ticket is $380\,€$ and a budget of 10000 euros is available for this operation. What is the probability that this budget is insufficient?
\end{enumerate}
Paper Questions