Scores on the SAT form a normal distribution with a mean of µ = 500 with σ = 100. If the state college only accepts students who score in the top 60% on the SAT, what is the minimum score needed to be accepted?

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Answer:

The minimum score needed to be accepted is 525.3.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

[tex]\mu = 500, \sigma = 100[/tex]

If the state college only accepts students who score in the top 60% on the SAT, what is the minimum score needed to be accepted?

The 60th percentile, which is the value of X when Z has a pvalue of 0.6. So it is X when Z = 0.253. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]0.253 = \frac{X - 500}{100}[/tex]

[tex]X - 500 = 0.253*100[/tex]

[tex]X = 525.3[/tex]

The minimum score needed to be accepted is 525.3.

The minimum score needed to be accepted is 525.3.

The first thing to solve a normal distribution problem is to find out the z-score.

What is a z-score?

A Z-score is a numerical measurement that describes a value's relationship to the mean of a group of values.

Formula to find out z-score

[tex]Z=\frac{X-A}{B}[/tex]

where,

X = observed value

A = mean value of the sample

B = standard deviation of the sample.

After we find the Z-score, we need to watch the z-score table and find the p-value associated with this z-score.

The p-value is the probability that the measured value is less than X.

It is given that

State college only accepts students who score in the top 60% on the SAT means p=0.60

From the table, the z-score that corresponds to the p-value 0.60 is 0.253

Now by using the above formula,

[tex]0.253=\frac{X-500}{100}\\\\X= 500+25.3=525.3[/tex]

The minimum score needed to be accepted is 525.3.

To get more about normal distribution problems refer to the link,

https://brainly.com/question/4079902