A pharmaceutical company wants to determine whether there is any difference among three different types ...

A   pharmaceutical company wants to determine whether there is any difference   among three different types of drugs (A, B and C) with respect to how long   they are retained in the body. Fifteen people are randomly assigned - five to   each drug. Data are collected on the number of days the drug remains in the   body before no trace of the drug is found. The data from these tests are   reported in the table below. Are there differences among these 3 drugs with   respect to how long they are retained in the body? Use a level of   significance of 0.01. DRUG A B C DAYS 81 82 68 IN THE 84 88 82 BODY 79 89 71   86 90 81 70 76 73        A B C   81 82 68   84 88 82   79 89 71   86 90 81   70 76 73