Answer:
0.64 is the proportion of students in the population who failed to notice the woman in the gorilla suit
Step-by-step explanation:
We are given the following in the question:
Total number of students, n = 25
Number of student who noticed woman in gorilla suit = 9
Number of student who failed to notice woman in gorilla suit, x = 25 - 9 = 16
We have to find the proportion of the students in the population who failed to notice the woman in the gorilla suit.
Formula:

0.64 is the proportion of students in the population who failed to notice the woman in the gorilla suit