csat-suneung 2011 Q7

csat-suneung · South-Korea · csat__math-humanities 3 marks Probability Definitions Probability Using Set/Event Algebra
A student named Chulsu participated in a design competition. Participants receive scores in two categories, and the possible scores in each category are one of three types shown in the table. The probability that Chulsu receives score A in each category is $\frac { 1 } { 2 }$, the probability of receiving score B is $\frac { 1 } { 3 }$, and the probability of receiving score C is $\frac { 1 } { 6 }$. When the event of receiving audience voting scores and the event of receiving judge scores are mutually independent, what is the probability that the sum of the two scores Chulsu receives is 70? [3 points]
CategoryScore AScore BScore C
Audience Voting403020
Judges504030

(1) $\frac { 1 } { 3 }$
(2) $\frac { 11 } { 36 }$
(3) $\frac { 5 } { 18 }$
(4) $\frac { 1 } { 4 }$
(5) $\frac { 2 } { 9 }$
A student named Chulsu participated in a design competition. Participants receive scores in two categories, and the possible scores in each category are one of three types shown in the table. The probability that Chulsu receives score A in each category is $\frac { 1 } { 2 }$, the probability of receiving score B is $\frac { 1 } { 3 }$, and the probability of receiving score C is $\frac { 1 } { 6 }$. When the event of receiving audience voting scores and the event of receiving judge scores are mutually independent, what is the probability that the sum of the two scores Chulsu receives is 70? [3 points]

\begin{center}
\begin{tabular}{ | c | c | c | c | }
\hline
Category & Score A & Score B & Score C \\
\hline
Audience Voting & 40 & 30 & 20 \\
\hline
Judges & 50 & 40 & 30 \\
\hline
\end{tabular}
\end{center}

(1) $\frac { 1 } { 3 }$\\
(2) $\frac { 11 } { 36 }$\\
(3) $\frac { 5 } { 18 }$\\
(4) $\frac { 1 } { 4 }$\\
(5) $\frac { 2 } { 9 }$