A researcher records the following number of birdcalls made during an experimental session with robins: 7.2 0.6 (M SD).Assuming these data are normally distributed,what is the probability that robins made more than 9 birdcalls during this experimental session?
A).9987
B).4987
C).0013
D)The probability is not listed in the unit normal table.

Question

A researcher records the following number of birdcalls made during an experimental session with robins: 7.2  0.6 (M  SD).Assuming these data are normally distributed,what is the probability that robins made more than 9 birdcalls during this experimental session?
A).9987 
B).4987 
C).0013 
D)The probability is not listed in the unit normal table.

Quizplus · Accepted Answer

To determine the probability that robins made more than 9 birdcalls, we need to standardize the data using the formula:

z = (x - μ) / σ

where:
x = 9 (since we want to know the probability of making more than 9 birdcalls)
μ = mean = 7.2
σ = standard deviation = 0.6

z = (9 - 7.2) / 0.6
z = 3

Using the unit normal table, the probability of getting a z-score of 3 or greater is 0.0013. Therefore, the probability that robins made more than 9 birdcalls during this experimental session is 0.0013 or approximately 0.13%. The correct choice is C.

A Researcher Records the Following Number of Birdcalls Made During