Respuesta :

Answer:

[tex]P(0.7<Z<1.4)[/tex]

And we can find this probability with the following difference:

[tex]P(0.7<Z<1.4)= P(Z<1.4)- P(Z<0.7)[/tex]

We can use the following commands on the ti 84

2nd>VARS>DISTR

And then we look for normalcdf and we input this:

normalcdf(0.7,1.4,0,1)

The other possible code would be:

normalcdf(-1000,1,4,0,1)-normalcdf(-1000,0.7,0,1)

And we got:

[tex]P(0.7<Z<1.4)=0.161[/tex]

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".  

Solution to the problem

For this case we want to find this probability:

[tex]P(0.7<Z<1.4)[/tex]

And we can find this probability with the following difference:

[tex]P(0.7<Z<1.4)= P(Z<1.4)- P(Z<0.7)[/tex]

We can use the following commands on the ti 84

2nd>VARS>DISTR

And then we look for normalcdf and we input this:

normalcdf(0.7,1.4,0,1)

The other possible code would be:

normalcdf(-1000,1,4,0,1)-normalcdf(-1000,0.7,0,1)

And we got:

[tex]P(0.7<Z<1.4)=0.161[/tex]

Answer: 0.1612

Step-by-step explanation:

P(0.7 <= Z <= 1.4)= P(Z<=1.4)- P(<=0.7)

= 0.91924 - 0.75804

= 0.1612