Question

The U.S. Bureau of Labor Statistics released hourly wage figures for various countries for workers in the manufacturing sector. The hourly wage was $30.67 for Switzerland, $20.20 for Japan, and $23.82 for the U.S. Assume that in all three countries, the standard deviation of hourly labor rates is $3.00.

Answer 1

a)

for normal distribution z score =(X-μ)/σx
here mean=       μ=	30.67
std deviation   =σ=	3.000
sample size       =n=	41

probability =

P(30<X<31)

=

P(-1.43<Z<0.7)=

0.758-0.0764=

0.6816

b)

here mean=       μ=	20.2
std deviation   =σ=	3
sample size       =n=	32
std error=σx̅=σ/√n=	0.5303

probability =

P(X>21)

=

P(Z>1.51)=

1-P(Z<1.51)=

1-0.9345=

0.0655

c)

probability =

P(X<22.75)

=

P(Z<-2.45)=

0.0071

d)

probability =

P(X<22.9)

=

P(Z<-2.12)=

0.0170