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2 years ago

Create a set of 5 positive numbers (repeats allowed) that have median 7 and mean 10.

Mathematics

1 answer:

damaskus [11]2 years ago

6 0

Answer:

Step-by-step explanation:

Two cases arise to obtain the median.

Case (1): Sample size (n) is odd

First, arrange the data in ascending order. Then, the median is the middle value and lies at the ${\left( {\frac{{n + 1}}{2}} \right)^{{\rm{th}}}}$ position.

Case (2): Sample size (n) is even

First, arrange the data in ascending order. Then, the median is the mean of the two data values that lie on and positions.

Formula for mean is, where is the sum of all observations and n is the total number of observations.

(1)

Use the below process to create a set of 5 positive numbers (repeats allowed) that have median 7 and mean 10.

1.Select the 5 ordered numbers with middle value 7.

2.Adjust the remaining 4 numbers other than 7 to get mean 10 without changing the order of the numbers.

Based on the process to select the 5 ordered numbers with middle value 7 and change the other ordered numbers to get the mean value 10.

(2)

The product of the mean and the total number of observations is obtained. Then, the sum of four observations is subtracted from the product.

Here, the first four numbers are (5, 6, 7, 8).

The last number by using mean 10 is,

$\begin{array}{c}\\\bar x = \frac{{5 + 6 + 7 + 8 + a}}{5}\\\\10 = \frac{{5 + 6 + 7 + 8 + a}}{5}\\\\50 = 26 + a\\\\a = 50 - 26\\=24\end{array}$

The last number is 24.

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