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A set of data has a mean of 10 and a standard deviation of 3.

(a) Each value in the data set has 6 added to it. Write down the value of
(i) the new mean;
(ii) the new standard deviation.
(b) Each value in the original data set is multiplied by 6.
(i) Write down the value of the new mean.
(ii) Find the value of the new variance.

User Torbatamas
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Answer:

Explanation:

(a) (i) The mean of the original data set is denoted as μ and the constant value being added to each data point is denoted as c.

The formula for the new mean is simply μ + c, so the new mean is μ + 6 = 10 + 6 = 16.

(a) (ii) The standard deviation of the original data set is denoted as σ. Adding a constant value to each data point does not change the spread of the data set, so the new standard deviation is still σ = 3.

(b) (i) The mean of the original data set is denoted as μ and the constant value being multiplied to each data point is denoted as k.

The formula for the new mean is μ * k, so the new mean is μ * 6 = 10 * 6 = 60.

(b) (ii) The variance of the original data set is denoted as V. To find the new variance after multiplying each data point by k, we can use the formula: k^2 * V.

So, the new variance is 6^2 * V = 36 * V.

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Here is a definition of each variable:

μ: The mean of a set of data is the sum of all the values divided by the number of values. It represents the average value of the data set.

σ: The standard deviation of a set of data is a measure of the spread of the data set about the mean. It is the square root of the variance.

V: The variance of a set of data is the sum of the squares of the deviations of each value from the mean, divided by the number of values. It is a measure of the spread of the data set about the mean, but it is measured in squared units.

c: A constant value added to each data point.

k: A constant value multiplied to each data point.

User Zeeshan Adnan
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