Answer: 4) 0.0062097
Step-by-step explanation:
Given : The length of a social media interaction is normally distributed with a mean of [tex]\mu=3[/tex] minutes and a standard deviation of [tex]\sigma=0[/tex] minutes.
Using the formula , [tex]z=\dfrac{x-\mu}{\sigma}[/tex], the z-value corresponding to x=4 will be :-
[tex]z=\dfrac{4-3}{0.4}=2.5[/tex]
Using the standard normal distribution table for z-value , the probability that an interaction lasts longer than 4 minutes will be :-
[tex]P(z>2.5)=1-P(z\leq2.5)=1-0.9937903=0.0062097[/tex]
Hence, the probability that an interaction lasts longer than 4 minutes = 0.0062097
