H ow many 200W/220V incandescent lamps connected in series

H ow many 200W/220V incandescent lamps connected in series would consume the same total power as a single 100W/220V incandescent lamp?

V₁ = V₂ = V_n =	200
	n

Power consumed in n bulbs connected in series

P₁ = n.		200		²	.	1	=	(200)²
		n				R₁		nR₁

But R₁ =	(200)²
	200

∴ P₁ =	200
	n

It must be equal to 100 watts (for bulb 100W/220V)

∴	200	= 100
	n

or n = 2