Two extrusion machines that manufacture steel rods are being compared. In a sample of 1000 rods taken from machine
a. 960 met specifications regarding length and diameter. In a sample of 600 rods taken from machine
b. 582 met the specifications. Machine B is more expensive to run, so it is decided that machine A will be used unless it can be convincingly shown that machine B produces a larger proportion of rods meeting specifications.