My coursework was to work out a parallel circuit on paper with values then to take it on to a breadboard to test , I can have 12v power and three LEDs and one resistor only . I have guessed the red LEDs VF and If as i don't have the information , VF 3v and If 20mA or 0.02a) The resistor value it unknow yet , so to work out R each LED has 20mA going though it, the current out thought the resistor is 3 x if so 3x20 = 60mA or 0.06a , next we have 12Vs the voltage across the Led is Vf 3v , R= Vs - Vf = / 3iF 12-3= 9 then 9 divided by 0.06 = 150 ohms . I am new to Electronics and the problem is the resistor gets very hot i am not sure what i am doing wrong .