To produce high quality steel one of two hardening agents A, B may be added

to the molten metal. Hardness of steel varies from batch to batch, so to test the

two agents 40 batches are each subdivided into two portions. For each batch agent

A is added to one portion, agent B to the other. To compare hardness, sharpened

specimens for each pair are used to make scratches on each other; that making the

deeper scratch on the other is the harder specimen. For the 40 pairs, that with

agent B is adjudged harder in 24 cases and that with agent A in 16. Is this sufficient

evidence to reject the hypothesis of equal hardness?(using R)