Question

what is the resistance of a 150 W light bulb running on a 120 V circuit ​

Answer 1

Volts (in volts) multiplied by current (in amps) gives you power (in watts).

So you have x volts * y amps = z watts.

Just rearrange for amps:

y amps = z watts / x volts

y = 150/120

y = 1.25 amps