First, 6 economists are selected for the triple rooms, yielding:
\(\binom{10}{6}\) ways.
Next, these 6 economists are divided into pairs for the 2 double rooms, which can be done in:
\(\frac{6!}{2^3 \cdot 3!}\) ways.
Consequently, the total number of ways is:
\(\binom{10}{6} \cdot \frac{6!}{2^3 \cdot 3!} = 210\)
Therefore, the correct answer is (a).