Answer :
Given:
Mean duration (μ) = 243.5 seconds
Standard deviation (σ) = 111.93 seconds
One of the songs is 389 seconds long (x)
To be able to determine the z-score, we will be using the following formula:
[tex]\text{ z = }\frac{\text{ x - }\mu\text{ }}{\sigma}[/tex]Where,
z = the z-score
x = the score
μ = the mean
σ = the standard deviation
We get,
[tex]\text{ z = }\frac{\text{ x - }\mu\text{ }}{\sigma}[/tex][tex]\text{ z = }\frac{\text{ 389 - 243.5 }}{\text{ 111.93}}[/tex][tex]\text{ z = }\frac{\text{ 145.5 }}{\text{ 111.93}}[/tex][tex]\text{ z = }1.2999195926\text{ }\approx\text{ 1.3}[/tex]Therefore, the z-score is 1.3