Question

In: Statistics and Probability

A concrete mix is designed to withstand 3000 pounds per square inch​ (psi) of pressure. The...

A concrete mix is designed to withstand 3000 pounds per square inch​ (psi) of pressure. The following data represent the strength of nine randomly selected casts​ (in psi).

3960​,

4090​,

3200​,

3000​,

2950​,

3830​,

4090​,

4040​,

3780

  

Compute the​ mean, median and mode strength of the concrete​ (in psi).

Compute the mean strength of the concrete. Select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.

A.The mean strength of the concrete is_______psi of pressure.

​(Round to the nearest tenth as​ needed.)

B.The mean does not exist.

Compute the median strength of the concrete. Select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.

A.The median strength of the concrete is_______psi of pressure.

​(Round to the nearest tenth as​ needed.)

B. The median does not exist.

Compute the mode strength of the concrete. Select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.

A.The mode of the strengths of the concrete is_______psi of pressure.

​(Round to the nearest tenth as​ needed.)

B. The mode does not exist.

Pick the best your answer(s).

Solutions

Expert Solution

Mean = sum(all values)/number of values      
            = 32940/9      
            = 3660      
Answer      
A.   The mean strength of the concrete is 3660 psi of pressure.      
      
Median is found using Excel function 'median'      
Median = median(all values)      
                = 3830      
Answer      
A.The median strength of the concrete is 3830 psi of pressure.      
      
Mode is the number which is repeated maximum number of times      
Here, 4090 is repeated max number of times that is 2 times      
Mode = 4090      
Answer      
A.   The mode of the strengths of the concrete is 4090 psi of pressure.      


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