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If one electrician is chosen at random, what is probability that this electrician earns over £{upper}?
\nProbability = [[0]](to 2 decimal places)
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\nProbability = [[0]](to 2 decimal places)
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\nrebelmaths
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\nConverting to $\\operatorname{N}(0,1)$
\n$\\simplify[all,!collectNumbers]{P(X > {upper}) = P(Z > ({upper} -{m}) / {s})} = P(Z>\\var{zupper}) = 1-P(Z<\\var{zupper})=1-\\var{p1} = \\var{prob2}$ to 2 decimal places.
\n\n
(b)
\n$\\simplify[all,!collectNumbers]{P({lower} < X < {upper}) = P(X < {upper})-P(X < {lower})}=P(Z<\\var{zupper})-P(Z<-\\var{zlower}) =\\var{p1}-\\var{p2} = \\var{prob3}$ to 2 decimal places.
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The salary of an electrician is normally distributed with mean £{m} and standard deviation £{s}.
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