Simon's copy of Probabilities from a normal distribution

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Question 1

The salary of an electrician is normally distributed with mean €46000 and standard deviation €7000.

a)

If one electrician is chosen at random, what is probability that this electrician earns over €49500?

Probability = Round your answer to 2 decimal places.Expected answer:(to 2 decimal places)

Score: 0/1

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b)

If one electrician is chosen at random, what is probability that this electrician earns between €35500 and €49500?

Probability = Round your answer to 2 decimal places.Expected answer:(to 2 decimal places)

Score: 0/2

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Advice

(a)

Converting to $\operatorname{N}(0,1)$

$\simplify[all,!collectNumbers]{P(X > {upper}) = P(Z > ({upper} -{m}) / {s})} = P(Z>\var{zupper}) = 1-P(Z<\var{zupper})=1-\var{p1} = \var{prob2}$ to 2 decimal places.

(b)

$\simplify[all,!collectNumbers]{P({lower} < X < {upper}) = P(X < {upper})-P(X < {lower})}=P(Z<\var{zupper})-P(Z<-\var{zlower}) =\var{p1}-\var{p2} = \var{prob3}$ to 2 decimal places.

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Simon's copy of Probabilities from a normal distribution - Electrician

Question 1

a)

b)

Advice