<p style="margin-bottom: 0.5rem">The thirty students in a class each took a Biology test. The marks obtained are shown in the table below.</p>
<div class="content-block content-block--table"><div class="table-container"><table style="table-layout: fixed; width: 400px;"><colgroup><col style="width: 100px;"><col style="width: 50px;"><col style="width: 50px;"><col style="width: 50px;"><col style="width: 50px;"><col style="width: 50px;"><col style="width: 50px;"></colgroup><thead><tr style="height: 38px;"><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>Marks</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(4\)</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(5\)</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(6\)</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(7\)</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(8\)</p></th><th style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(10\)</p></th></tr></thead><tbody><tr style="height: 38px;"><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>Frequency</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(2\)</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(5\)</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(11\)</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(8\)</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(3\)</p></td><td style="height: 38px; min-height: 38px; text-align: center; --cell-justify: center"><p>\(1\)</p></td></tr></tbody></table></div></div>
<p>Calculate the unbiased estimates of the population mean and variance.  </p>

The thirty students in a class each took a Biology test. The marks obtained are shown in the table below.

Calculate the unbiased estimates of the population mean and variance.  

Statistical Estimates of Biology Test Marks

Statistical Estimates of Biology Test Marks