It Makes Cents
Below is a histogram of the distribution of the ages of the pennies from
my parents’ penny jar.
x = the age of one randomly selected penny
u x = 19.22
σ x = 12.62
What is the shape of the distribution above?
Can we use normal curve calculations to compute the probability that the
age of a randomly selected penny will exceed 10 years?
Below is a histogram of the sampling distribution of sample means for
size n=2.
Mean and standard deviation of the sampling distribution:
x = the mean age of two randomly selected pennies
ux = µx =
σx =
σx
=
n
What is the shape of the distribution above?
Can we use normal curve calculations to compute the probability that the
average age of two randomly selected pennies will exceed 13 years?
Below is a histogram of the sampling distribution of sample means for
size n=4.
Mean and standard deviation of the sampling distribution:
x = the mean age of four randomly selected pennies
ux =
σx =
What is the shape of the distribution above?
Can we use normal curve calculations to compute the probability that the
average age of four randomly selected pennies will exceed 13 years?
Below is a histogram of the sampling distribution of sample means for
size n=30.
Mean and standard deviation of the sampling distribution:
x = the mean age of 30 randomly selected pennies
ux =
σx =
What is the shape of the distribution above?
Can we use normal curve calculations to compute the probability that the
average age of thirty randomly selected pennies will exceed 13 years?
1.)
What is the probability that one penny chosen at random from
the population will be at least 20 years old?
x = the age of one randomly selected penny
P(x ≥ 20)=
2.)
What is the probability that an SRS of n=50 pennies will have a
mean age of 20 or more years old?
x = the mean age of 50 randomly selected pennies
P( x ≥ 20) =