When the Wheatstone bridge shown is used to find value of

When the Wheatstone bridge shown is used to find value of resistance R_x, the Galvanometer G indicates zero current when R₁ = 50Ω, R₂ = 65Ω & R₃ = 100Ω. If R₃ is known with ± 5% tolerance on its nominal value of 100Ω, what is range of R_x in ohms?

For balanced wheat stone bridge R₁R_X = R₂R₃

R_x =	R₂R₃	.........(i)
	R₁

R₃ has tolerance of ± 5%
Value of R₃ can be = 100 ± 5% of 100
= 100 ± 5 =[95, 105]
Value of R_X if R₃ = 95Ω

R_x =	65 × 95	= 123.5 Ω
	50

Value of R_X if R₃ = 105Ω

R_x =	65 × 105	= 136.5 Ω
	50

Range of R_X in ohms = [123.5, 136.5]