<PRE><B>Question 1159131</B>
&lt;br&gt;
Of course you can use the formal definition of mean to write and solve an equation to solve the problem.&lt;br&gt;
If that kind of formal solution method is not required, there are other ways that can get you to the answer faster and with less work.  Here is my preferred method.&lt;br&gt;
The 1st number is 10 short of the mean.
The second number is 11 over the mean.
The third number is 5 short of the mean.&lt;br&gt;
Together, the first three numbers are 4 short of the mean.&lt;br&gt;
That means the fourth number is 4 over the mean.&lt;br&gt;
ANSWER: 25+4 = 29&lt;br&gt;
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