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Use technology or a z-score table to answer the question. Scores on a standardized exam are normally distributed with a mean of 59 and a standard deviation of 8. Consider a group of 5000 students. Approximately how many students will score less than 67 on the exam?

User AlexZ
by
7.4k points

2 Answers

4 votes

Answer:

Answer:

C

Step-by-step explanation:

Find P(X > 67)

using ( x - mean )/ standard deviation again you will get thi(1) which is equal to 0.8413....

0.8413 x 5000 is 4207

Explanation:

User Ankit Ostwal
by
6.9k points
5 votes

Answer:

Approximately 4200 students will score less than 67 on the exam.

Explanation:

Given:

Scores are normally distributed.

Mean score is,
\mu=59

Standard deviation is,
\sigma=8

Score is,
x=67

Total number of students,
n=5000

Now, the z score is given as:


z=(x-\mu)/(\sigma)\\\\z=(67-59)/(8)=(8)/(8)=1

Since, the score is less than 67, therefore, z-score must be less than 1. So,


z<1

From the z-score table, we observe that for z < 1, the population is 0.8413 or 84.13 % of the total population.

Therefore, the number of students scoring less than 67 is given as:


Number\ less\ than\ 67\ score=0.8413* 5000=4206.7\approx 4200

So, approximately 4200 students out of 5000 will get a score less than 67.

User Eddie Deyo
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