5 Ohm 3 Ohm 2 Ohm R=?

6.2 ohm

Explanation:

Let R1 = 5 ohm

R2= 3 ohm

R3= 2 ohm

Since R3 and R2 are parallel then net resistance R' is given by

1/R' = 1/R2 + 1/R3

1/R' = 1/3 + 1/2

1/R' = 5/6

then

R' = 6/5 = 1.2 ohm

Now R1 and R' are in series, so

R = R1 + R'

R = 5 + 1.2

R = 6.2 ohm

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