Given a set ${4, - 2, - 12, 5, x}$ ${4,-2,-12,5,x}$ , for what x would the mean of the set be -5?

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Given a set ${4, - 2, - 12, 5, x}$ ${4,-2,-12,5,x}$ , for what x would the mean of the set be -5?

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Answer 1 · 2015-12-17T07:29:05

$\times - 262$ $color(white)(xx)-262$

Explanation:

$\times ¯ a = \frac{1}{n} n \sum i = 1 a_{i}$ $color(white)(xx)bar a =1/nsum_(i=1)^n a_i$ (the mean of a set of n data points)

$\times - 5 = \frac{1}{5} 5 \sum i = 1 a_{i}$ $color(white)(xx)-5=1/5sum_(i=1)^5 a_i$
$\Rightarrow \frac{x - 12 - 2 + 4 + 5}{5} = - 5$ $=>(x-12-2+4+5)/5=-5$

Multiply both sides by $5$ $5$
$\times 5 \cdot \frac{x - 12 - 2 + 4 + 5}{5} = 5 \cdot (- 5)$ $color(white)(xx)color(red)(5*)(x-12-2+4+5)/5=color(red)(5*)(-5)$
$\Rightarrow x - 5 = - 25$ $=>x-5=-25$

Add $5$ $color(red)5$ to both sides
$\times x - 5 + 5 = - 25 + 5$ $color(white)(xx)x-5color(red)(+5)=-25color(red)(+5)$
$\Rightarrow x = - 20$ $=>x=-20$

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Given a set ${4, - 2, - 12, 5, x}$ ${4,-2,-12,5,x}$ , for what x would the mean of the set be -5?

1 Answer

Explanation:

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Science

Math

Humanities

... and beyond

Given a set {4,-2,-12,5,x} {4,−2,−12,5,x} {4,-2,-12,5,x} , for what x would the mean of the set be -5?

1 Answer

Explanation:

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Given a set ${4, - 2, - 12, 5, x}$ ${4,-2,-12,5,x}$ , for what x would the mean of the set be -5?