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Question
Given the resistances of 1 Ω, 2 Ω, 3 Ω, how will be combine them to get an equivalent resistance of (6/11) Ω?
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Solution
Equivalent resistance, R' = `6/11` Ω
Consider the series combination of the resistors, as shown in the given circuit.

Equivalent resistance of the circuit is given by,
R' = `(1 xx 2 xx 3)/(1 xx 2 + 2 xx 3 + 1 xx 3)`
= `6/11` Ω
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