Material Strength

In the manufacture of soft contact lenses the strength of the lens should not be too high. The following table contains the strength index (hardness and elasticity) of lenses produced using materials from three different suppliers.

Study questions and activities.

Compute the mean and standard deviation for each supplier, and construct boxplots for the data.
Describe the deviation of material strength for the three suppliers.
Which supplier appears to provide material that produces lenses having reliably low strength?