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How to calculate the total resistance?
Can anyone help kind of confused here

You can replace R1, R2 by a resistance (name it R') with value R' = R1//R2.
The same thing for R3, R4, R''=R3//R4.
Now you have R' in series with R'', i.e: total resistance R = R'+R''=(R1//R2)+(R3//R4).

First find resistance of the resistors in parallel.

Find resistance of R1 and R2 in parallel.
(R1 X R2) / (R1 + R2) = RP1.

Find resistance of R3 and R4 in parallel.
(R3 X R4) / (R3 + R4) = RP2.


Then you have a series circuit. With a series circuit you simply add all the resistance for total circuit resistance.

RP1 + RP2 = Total circuit resistance

hkstroud - you need to learn to use parentheses. What you wrote is this:

R_1 \times \frac {R_2}{R_1} + R_2 = RP_1

which is equivalent to:

2R_2 = RP_1

and that's clearly incorrect.

What you should have written is:

R 1 x R2/(R1+R2) = RP1, or


\frac {R_1 R_2}{R_1 + R_2} = RP_1

To the the OP: hope this helps.

Is that better?

Is that better?

Much!