Respuesta :
Answer:
90% of people getting married for the first time get married before 32 years.
Step-by-step explanation:
The average age for a person getting married for the first time is 26 years i.e. [tex]\mu=26[/tex]
The ages for the first marriages have a normal distribution with a standard deviation of about 4 years i.e. [tex]\sigma = 4[/tex]
90% of people getting married for the first time.
The z-value at 90% confidence interval is z=1.64.
The z-score formula is given by,
[tex]z=\frac{x-\mu}{\sigma}[/tex]
Where, x is the required sample mean or age.
Substitute the values,
[tex]1.64=\frac{x-26}{4}[/tex]
[tex]1.64\times 4=x-26[/tex]
[tex]6.56=x-26[/tex]
[tex]x=6.56+26[/tex]
[tex]x=32.56[/tex]
Therefore, 90% of people getting married for the first time get married before 32 years.
