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Question
Find the equivalent resistance between points A and B.

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Solution
Let RP be the equivalent resistance of the resistors 12 Ω, 6 Ω and 4 Ω connected in parallel. Hence, we have
`1/R_p = 1/12 + 1/6 + 1/4`
`= (1+ 2+3)/12 = 1/2`
Rp = 2Ω
Therefore, the equivalent resistance of the circuit is
2Ω + Rp + 5Ω = 2Ω + 2Ω + 5Ω = 9Ω
Thus, the equivalent resistance between points A and B is 9Ω .
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