Draw two lamps and a battery of 12 volts calculate the current in each lamp and the voltage across each lamp if the resistance are 40 and 60 ohms respectively
in series, R = 40+60 = 100
current is the same in both lamps: I = 12/100 = 0.12
The voltage is 40*0.12 or 60*0.12
In parallel, I = 12/40 or 12/60
the voltage is 12V across each lamp.