Given the set: ${1,13,-7,8,x,-2,-9,2}$ , for what x would the mean of the set be 0?

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Answer 1 · 2015-12-28T18:18:29

$x=-6$

$color(white)(xx)bar a =1/nsum_(i=1)^n a_i$ (the mean of a set of n data points)

$color(white)(xx)0=1/8sum_(i=1)^8 a_i$
$=>(x-9-7-2+1+2+8+13)/8=0$

Multiply both sides by $color(red)8$
$color(white)(xx)color(red)(8xx)(x-9-7-2+1+2+8+13)/8=color(red)(8xx)(0)$
$=>x+6=0$

Add $color(red)(-6)$ to both sides
$color(white)(xx)x+6color(red)(-6)=0color(red)(-6)$
$=>x=-6$

Given the set: {1,13,-7,8,x,-2,-9,2} {1,13,-7,8,x,-2,-9,2} , for what x would the mean of the set be 0?