<PRE><B>Question 73299</B>
Mr.Nelson lost one of his students test papers. He knows that the other 4 students scored as follows: 12,20,21,12. He know that the average score is 19.4.What the score on the missing paper
:
Let x = missing paper score:
{{{(12 + 20 + 21 + 12 + x)/5}}} = 19.4
;
Mult equation by 5 and you have:
12 + 20 + 21 + 12 + x = 5(19.4)
:
65 + x = 97
:
x = 97 - 65
:
x = 32 score of the missing paper
:
:
Check:
{{{(12 + 20 + 21 + 12 + 32)/5}}} = 
:
{{{97/5}}} = 19.4</PRE>