Step 1: Convert the statement into an equation.
Let the fee be $f$ and the number of participants be $p$. Then
\[
fp = 38950,\qquad 46 \le p \le 99,\qquad p\in\mathbb{Z}.
\]
Step 2: Test the options (must divide 38950 and yield $p$ in range).
\[
p=\frac{38950}{f}.
\]
For $f=₹410$: $p=\dfrac{38950}{410}=95$ (integer, and $46\le 95\le 99$)\ ⇒\ \text{valid}.
For $f=₹450$: $p=\dfrac{38950}{450}\notin\mathbb{Z}$\ ⇒\ \text{invalid}.
For $f=₹500$: $p=\dfrac{38950}{500}=77.9\notin\mathbb{Z}$\ ⇒\ \text{invalid}.
For $f=₹510$: $p=\dfrac{38950}{510}\notin\mathbb{Z}$\ ⇒\ \text{invalid}.
Step 3: Conclude.
Only $f=₹410$ gives an integer participant count within the required range.
\[
\boxed{\text{Participants' fee }=\ ₹410}
\]