A researcher selects a sample of 49 participants from a population with a mean of 12 and a standard deviation of 3.5. What is the probability of selecting a sample mean of 13 or larger from this population

Respuesta :

Answer:

The probability of selecting a sample mean of 13 or larger from this population is 0.0228

Step-by-step explanation:

A researcher selects a sample of 49 participants from a population with a mean of 12 and a standard deviation of 3.5.

[tex]n = 49[/tex]

[tex]\mu = 12[/tex]

[tex]\sigma = 3.5[/tex]

We are supposed to find the probability of selecting a sample mean of 13 or larger from this population i.e.[tex]P(x\geq 13)[/tex]

[tex]Z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]Z=\frac{13-12}{\frac{3.5}{\sqrt{49}}}[/tex]

Z=2

Refer the z table

[tex]P(Z<2)=0.9772[/tex]

[tex]P(x\geq 13)=1-P(Z<2)=1-0.9772=0.0228[/tex]

Hence the probability of selecting a sample mean of 13 or larger from this population is 0.0228