A researcher measures the number of tasks completed by participants during a 5-minute multitasking session.If the number of tasks completed is distributed normally as 6.3 1.0 (M SD)tasks,then what is the probability that participants completed less than 8 tasks?
A).0446
B).9554
C).4554
D)The probability is not listed in the unit normal table.

Question

A researcher measures the number of tasks completed by participants during a 5-minute multitasking session.If the number of tasks completed is distributed normally as 6.3  1.0 (M  SD)tasks,then what is the probability that participants completed less than 8 tasks?
A).0446 
B).9554 
C).4554 
D)The probability is not listed in the unit normal table.

Quizplus · Accepted Answer

We need to find the probability that participants completed less than 8 tasks. Let X be the number of tasks completed by a participant in a 5-minute multitasking session. We want to find P(X < 8).

Using the normal distribution, we can standardize X as follows:

Z = (X - μ) / σ

Where μ = 6.3 and σ = 1.0

So, we have:

Z = (8 - 6.3) / 1.0 = 1.7

Now, we need to find the area under the standard normal curve to the left of Z = 1.7. From the unit normal table, we find that the area is approximately 0.9554.

Therefore, the probability that participants completed less than 8 tasks is 0.9554 or about 95.54%. The best choice is B.

A Researcher Measures the Number of Tasks Completed by Participants