Question 798454
An average = ( sum of the data ) / ( the number of samples )
Before the other student returns, let {{{ s }}}
= the sum of the test scores
{{{ 75 = s / 24 }}}
{{{ s = 75*24 }}}
{{{ s = 1800 }}}
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Let {{{ x }}} = the score that the returning student got
{{{ 76 = ( 1800 + x ) / 25 }}}
{{{ 25*76 = 1800 + x }}}
{{{ x = 1900 - 1800 }}}
{{{ x = 100 }}}
The absentee student got 100%