Quiz scores The scores on Ms. Martin’s statistics quiz had a mean of 12 and a standard deviation of 3Ms. Martin wants to transform the scores to have a mean of 75 and a standard deviation of 12What transformations should she apply to each test score? Explain your answer.

Short Answer

Expert verified

Each score to be multiplied by 4 and then added with 27

Step by step solution

01

Given information

Before transformations:

Mean, μ=12

Standard deviations, σ=3

After transformations: μN=75

New Standard deviations,σN=12

02

Calculation

The standard deviation was used to account for the distance between the numbers in the first stage.

When each score is multiplied by four, the distance between the numbers increases by four times.

When the distance between two numbers is multiplied by four, the rate of deviations is multiplied by four.

As a result, the standard deviation is converted to 12 instead of 3

In the next step,

According to the first phase, the mean has been changed to 48 instead of 12

However, we must reach a 75th percentile average.

To do this, we must add 27 to each score, resulting in a 75-point average.

Whereas,

The standard deviation and distance between numbers will remain unchanged.

Therefore,

To carry out the modifications,

Ms. Martin must multiply each score by four and then add 27to each result.

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