Question

Two machines, C1 and C2, are making pins which must have a diameter of 8 cm ± .01 cm or they are rejected. Dotplots of 50 pins from each machine are displayed below. They are both on the same scale.

By simply looking at the dotplots, i.e. without doing any calculations or counting, compare the distributions of the two machines:

In what sense is machine C1 ‘better’ at producing pins? Justify your argument.