Need Some More Help With Cirucits Again

So here, again, I'm stuck and dumbfounded,
so please help if possible
here is the problem word for word

so since the Voltage Total = 20v and the total voltage put out by the three resistors is only 17.7 you're missing a resistor.
So I added one in and its voltage is 2.3v (Vt - x = 20v - 17.7v = 2.3v)

So the four resistors have voltages of 8.8, 5.6, 3.3, and 2.3

now i need to devise a cirucuit

but before i can do that I need to figure out the Resistance values of each resistor, and thus I am stumped.

Any ideas?

 

Briefly looked at your text, i have an LED calculator on my site here which can be used for any other device as long as yyou know forward voltage etc.
http://dsminded.com/current_limiting_led_calculator/

EDIT:

I'll have a look a bit later, and try and possibly get you a scematic. Am i right in thinking you have 20v supply, and need it off into 3 different rails (with 8.8, 5.6, 3.3 respectivly)?


The devider curcuit will hav an output voltage/s that is a fraction of its input voltage.

 

i don't think your website would help because i do not have any LED's in the circuit,

and you are correct except its a 20v supply running through 4 resistors (8.8, 5.6, 3.3, and 2.3)

i need to find the values of those four resitors

 

V=IR will give you the answer.

 

ohm's law cannot work without a current,
if i were to find I it would not work because I do not have a resistance
and a current can not be found without at least one resistor value,

so i think i have to go through all my resistors, calculate values, and plug and chug for a few hours

 

guessing and calculating would be the way to go, since only 1 out of the 3.

 

unfortunetly, that is how it was,

only took about 6 hours with a set of about 40 resistors but i got it

 

Curious as to what year you are, and if this is your first circuits course?

 

I took electronics in 8th grade, not involving protoboards, but with actual circuits, the teacher was not great,
i also took hardware in 12th grade,
I'm technically a college sophomore, except i started college with 10 credits so i'm a sophomore in college

Circuitry is not my thing,
Its a prerequisite for one of my classes I'm taking next year

I'm also 18, if that is what you meant

 

No no, the college thing was what I was asking. I just graduated in Electrical Engineering, which is why I was wondering. What course is this a prereq for?

 

honestly I'm undecided at the moment,
Its for a Computer Engineering class,
but I'm currently majoring in Electrical Engineering and Technology

but I'm sure that will change