Exercise $2$ : Mixing $""$ solve it on paper""

A past material was mixed in presence of $17\%$ tracer. After $7$ minutes of mixing, $6$ samples were randomly taken from the mix and analyzed. The measured concentrations in the sample are illustrated in the below table. Calculate the mixing and state weather the mixing is good or not.

$\backslash$table$[[$Sample No$.,\backslash$table$[[$Concentration$],[($wt$.\%)]]],[1,15\mathrm{.}3],[2,17\mathrm{.}2],[3,16\mathrm{.}9],[4,15\mathrm{.}4],[5,15\mathrm{.}8],[6,17\mathrm{.}8]]$