In an electric circuit, three resistors with resistances 2 ohms, 5 ohms and 6 ohms are connected in parallel. In this case, if R is the combined resistance of these three resistors, then the reciprocal of R is equal to the sum of the reciprocals resistors. What is R value?
Choose the correct answer.
A) 13/15 ohms	B) 15/13 ohms	C) 5/8 ohms	D) 3/7 ohms	E) 45/18 ohms
The wording is a bit confusing, though basically we are told that 1/R = 1/2 + 1/5 + 1/6, from which it follows that R=13/15ohms   Option: 13/15 ohms
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In an electric circuit, three resistors with resistances 2 ohms, 5 ohms and 6 ohms are connected in parallel. In this case, if R is the combined resistance of these three resistors, then the reciprocal of R is equal to the sum of the reciprocals resistors. What is R value?