taiwan-gsat 2025 Q11

taiwan-gsat · Other · gsat__math-b 5 marks Geometric Probability
The Earth is a sphere. Five points $A , B , C , D , E$ on the Earth's surface have the following latitude and longitude coordinates, for example, point $A$ is located at longitude 0 degrees, north latitude 60 degrees.
LocationLongitude 0 degreesLongitude 180 degrees
North latitude 60 degrees$A$$B$
North latitude 30 degrees$C$$D$
Latitude 0 degrees$E$

A great circle is the circle formed by the intersection of a plane passing through the center of the sphere with the sphere's surface. The shorter arc formed by two distinct points on the sphere on a great circle is the shortest path. Based on the above, select the correct options.
(1) ``The shortest path length from the North Pole to $A$'' equals ``the shortest path length from the North Pole to $B$''
(2) ``The shortest path length from $A$ to $B$'' equals ``the shortest path length from $C$ to $D$''
(3) The shortest path from $A$ to $E$ must pass through $C$
(4) The shortest path from $C$ to $D$ must pass through the North Pole
(5) The ratio of ``the shortest path length from $E$ to the North Pole'' to ``the shortest path length from $C$ to $D$'' is $2 : 3$
The Earth is a sphere. Five points $A , B , C , D , E$ on the Earth's surface have the following latitude and longitude coordinates, for example, point $A$ is located at longitude 0 degrees, north latitude 60 degrees.

\begin{center}
\begin{tabular}{ | c | c | c | }
\hline
Location & Longitude 0 degrees & Longitude 180 degrees \\
\hline
North latitude 60 degrees & $A$ & $B$ \\
\hline
North latitude 30 degrees & $C$ & $D$ \\
\hline
Latitude 0 degrees & $E$ &  \\
\hline
\end{tabular}
\end{center}

A great circle is the circle formed by the intersection of a plane passing through the center of the sphere with the sphere's surface. The shorter arc formed by two distinct points on the sphere on a great circle is the shortest path. Based on the above, select the correct options.\\
(1) ``The shortest path length from the North Pole to $A$'' equals ``the shortest path length from the North Pole to $B$''\\
(2) ``The shortest path length from $A$ to $B$'' equals ``the shortest path length from $C$ to $D$''\\
(3) The shortest path from $A$ to $E$ must pass through $C$\\
(4) The shortest path from $C$ to $D$ must pass through the North Pole\\
(5) The ratio of ``the shortest path length from $E$ to the North Pole'' to ``the shortest path length from $C$ to $D$'' is $2 : 3$