9
10
20
11
When the resistors are connected in series, the total resistance is nR + R = R(n+1). The current drawn is given by Ohm's law:
I = E / (R(n+1))
When the resistors are connected in parallel, the total resistance is R/n. The current drawn is:
10I = E / (R/n + R) = E / (R(1/n + 1)) = nE / (R(1+n))
We have two equations:
Substitute equation (1) into equation (2):
10 * [E / (R(n+1))] = nE / (R(1+n))
10 = n
Therefore, the value of n is 10.
Option 2 is correct