# Normal Distribution Stats

Let $$X \sim N(65,20)$$

Find correct to $3$ Decimal Place the value of $x$ such that $Pr(X>x) = 0.43$

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What have you tried? Which tools are you allowed to use? – Stefan Hansen Feb 6 at 9:34

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Down-voted because the OP didn't indicate any interaction with their question. – Rustyn Yazdanpour Feb 6 at 9:47
@StefanHansen i've gotten to $\frac {x-65}{2(5)^{1/2}} =0.1764$ and hence $x = 67.789$ ?? – Sam Feb 6 at 10:05
– Stefan Hansen Feb 6 at 10:09
im not 100% sure where i've gone wrong with my working out? – Sam Feb 6 at 10:15
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## 1 Answer

Making my comment as an answer. The equation $$\frac{x-65}{\sqrt{20}}=0.1764$$ you proposed is correct. However, the solution to this is $$0.1764\cdot \sqrt{20}+65\approx 65.789$$ and not $67.789$.

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