Answer: 0.8956
Step-by-step explanation:
Given: The daily surface concentration of carbonyl sulfide on the Indian Ocean is normally distributed, with a mean [tex]\mu=100[/tex] picomoles per liter and standard deviation of [tex]\sigma=3.5[/tex] picomoles per liter.
Let X be the daily surface concentration of carbonyl sulfide.
The probability that on a randomly selected day, the surface concentration of carbonyl sulfide on the Indian Ocean is less than 13.5 picomoles per liter [tex]= P(X<13.5)[/tex]
[tex]=P(\dfrac{X-\mu}{\sigma}>\dfrac{13.5-9.1}{3.5})\\\\=P(Z<1.257)\\\\= 0.8956\ \ \ [\text{By p-value table}][/tex]
Hence, the required probability = 0.8956