The sample observations on stabilized viscosity of asphalt specimens are 2781, 2900, 3013, 2856 and 2888. Suppose that for a particular application, it is required that true average viscosity be 3000. Does this requirement appear to have been satisfied? State and test the appropriate hypothesis at alpha = 0.05.

Respuesta :

Answer:

There is no enough evidence that the viscosity is not 3000. The viscosity is not significantly different from 3000.

Step-by-step explanation:

We have to perform an hypothesis test on the mean.

The null and alternative hypothesis are:

[tex]H_0: \mu=3000\\\\H_1:\mu\neq3000[/tex]

The significance level is 0.05.

The mean of the sample is:

[tex]M=(1/5)*(2781+2900+3013+2856+2888)=2887.6[/tex]

The standard deviation of the sample is:

[tex]s=\sqrt{\frac{1}{5-1}*[(2781-2887.6)^2 +(2900-2887.6)^2 +...]}=84.0[/tex]

The statistic t can be calculated as:

[tex]t=\frac{M-\mu}{s} =\frac{2887.6-3000}{84} =-1.338[/tex]

The degrees of freedom are [tex]df=N-1=5-1=4[/tex]

The P-value for t=-1.338 and df=4 is P=0.2519. The P-value is greater than the significance level, so it failed to reject the null hypothesis.

There is no enough evidence that the viscosity is not 3000.