The probability that an interaction lasts longer than 4 minutes is 0.0062.
<h3>What is probability theory?</h3>
probability theory in mathematics focus on the analysis of random phenomena and this theory let us know that the outcome of a random event cannot be determined before it occurs.
z = (4 - 3)/.4
z = 1/.4
z = 2.5
0.0062
Hence The probability that an interaction lasts longer than 4 minutes is 0.0062.