can i use one resistor on 11 leds?

I'm trying to convert the dash bulbs in my cluster to LEDs. I have 11 tiny bulbs that I need to replace with LEDs. The bulbs all share the same power circuit and ground. So I'm trying to find out if I can just put one resistor in the main power feed of the bulb circuit. If the resistor calculator I found online is correct, I can use one 1/2 watt 47 ohm resistor. The LEDs I'm using are 3.5volt 20ma. So would this work using only one resistor, or will I have to put a 470 ohm on each and every LED soldered on the board??

anybody?

You can do it with one resistor for the lot, BUT - if you lose too many LEDs, you'll blow the rest. V=IR => R = V/I = 10V/(11x20mA) = 10/.22 = 45R = 47 Ohms or 56 Ohms for a bit of margin. P = I^2 x R = I x I x R = .22 x .22 x 47 = 2.27 => 5W. So a 5 Watt 47 (or 56) Ohm resistor.

thanks

here is a goo sight to make your own leds. I do use if from time to time to make sure i get the correct resistance http://metku.net/index.html?path=mods/ledcalc/index_eng if you scroll down it will give you all types of ways to connect your leds with including the calculator