If R is the total resistance of three resistors, connected in parallel with resistances R₁, R₂, R₃ then
1/R = 1/R₁ + 1/R₂ + 1/R₃
If the resistances are measured in ohms as R₁ = 4Ω, R₂ = 8Ω, and R₃ = 80Ω, with a possible error of 0.5% in each case, estimate the maximum error in the calculated value of R.
