Question 826003
I think this is what you're asking:
{{{ ( 3 + 7 + 4 + x + 2 + 11 ) / 6 = 5 }}}
where {{{ 5 }}} is the average of the given
numbers including the missing number
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There are {{{6}}} numbers, so you add them
and divide by {{{6}}} to get the average
Multiply both sides by {{{ 6 }}}
{{{ 3 + 7 + 4 + x + 2 + 11 = 6*5 }}}
{{{ 27 + x = 30 }}}
{{{ x = 3 }}}
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check:
{{{ ( 3 + 7 + 4 + 3 + 2 + 11 ) / 6 = 5 }}}
{{{ 30/6 = 5 }}}
{{{ 5 = 5 }}}
OK