Question

A scientist was testing to determine if the resistance of electrical wire can be reduced by alloying the wire. She obtained 4141values for standard wiring and found the average to be x¯=0.188x¯=0.188 ohm and sx=0.056sx=0.056 ohm, and she obtained 4141 values for alloyed wire which resulted in y¯=0.066y¯=0.066 ohm and sy=0.065sy=0.065 ohm.

With this data construct a 95%95% confidence interval for the true difference between the average resistance of the two kinds of wire.

____<μX----μY<_____

Answer 1

Given that,

For standard wire :

For alloyed wire :

Using TI-84 calculator we get, the 95%95% confidence interval for the true difference between the average resistance of the two kinds of wire is,