How Do You Calculate Current and Power in Parallel Resistors?

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To calculate the current and power in parallel resistors, first determine the total resistance using the formula 1/(R.total) = 1/(R.1) + 1/(R.2). Given a 64-ohm resistor with a current of 3A, apply Ohm's law (V = IR) to find the voltage across the resistors. Use this voltage to calculate the current through the 42-ohm resistor with I = V/R. Finally, total power can be calculated by summing the power across both resistors, where power (P) is given by P = IV for each resistor.
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Homework Statement



2) 2 resistors, 42 and 64 ohms, are connected in parallel. The current through the 64 resistor is 3A. Determine the current in the other esistor and what is the total power supplied by the two resistors?

Homework Equations





The Attempt at a Solution




2) How could i possibly have enough info to do this one?
 
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1, Whats the overall resistance of 2 resistors in parallel (extend this to 3 resistors)?
 
The resistance is not the same if the pieces are connected in parallel.

Resistors connected in parallel follow the law

1/(R.total)=1/(R.1)+1/(R.2)+1/(R.3)...

Where R.total is the total resistanse and R.1 is the resistanse of the first resistor, R.2 is the resistanse of the second resistor etc. etc.
 
thanks figured that one out, can you help me with the second one?
 
Assume the same voltage across both resistors.
Then V=IR for the known and I =V/R for the unknown.
(it should also be obvious how to skip a step)
 

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