Deciding base resistor for transistor switch circuit
The formulation is correct. You must be careful with the \$h_{fe}\$ value you use. Search the device data sheet curve \$h_{fe}\$ vs. collector current, to the value of \$h_{fe}\$ in saturation state.

EDIT: from the datasheet



You must use the lower curve to size the output current and by the ratio 
$$
\dfrac{I_C}{I_B}=1000
$$
obtain the required value of base current.
For the saturation condition, the value of \$h_{fe}\$ is lower than for the condition of linear operation, so may the value selected for the base resistance is rather high.