# Can someone help me with the task.. very difficult

• Jan 19th 2013, 08:14 AM
gary147
Can someone help me with the task.. very difficult
Once the ground-workers made the concrete you took samples as the concrete was poured into the foundations. These samples were taken to the laboratory and after seven days the results returned were as follows:
Ultimate Strength of Concrete Cubes (N/mm˛)
15, 15, 10, 11, 20, 20, 11, 12, 18, 18, 12, 12, 13, 13, 13, 18, 19, 19, 14, 14, 14, 14, 13, 13, 13, 14, 14, 14, 14, 19, 19, 15, 15, 15, 15, 15, 15, 15, 15, 17, 17, 17, 17, 17, 16, 16, 16, 16, 16, 16.
With this data:
1. Write the data sequentially
2. Put the data into a tally table
3. Then order it for a coding table ready to work out the mean and standard deviation

Use the following:

Chosen Value 15.000 N/mm˛

Unit Value: 1.0 N/mm˛
• Jan 19th 2013, 10:48 AM
gary147
Re: Can someone help me with the task.. very difficult
• Jan 19th 2013, 11:23 AM
HallsofIvy
Re: Can someone help me with the task.. very difficult
What, exactly, do you find "very difficult"? You are asked to write them in sequence. Do you understand what that means? You are two write this list from smallest number to largest. Surely you can do that? What is the smallest number in the list 15, 15, 10, 11, 20, 20, 11, 12, 18, 18, 12, 12, 13, 13, 13, 18, 19, 19, 14, 14, 14, 14, 13, 13, 13, 14, 14, 14, 14, 19, 19, 15, 15, 15, 15, 15, 15, 15, 15, 17, 17, 17, 17, 17, 16, 16, 16, 16, 16, 16? What is the next smallest?

You are asked to make a "tally list". Do you know what that is? List the numbers, 10, 11, ....18, 19, 20 vertically and beside each put "tally marks" to show how many times that number is on the list.

You are asked to put these numbers in a "coding table ready to work out the mean and standard deviation". Do you know what those mean? The "mean value" is the "average value: sum all those numbers and divide by 50 (there are 50 numbers unless I have counted wrong. Was that what you got?) The "coding table", each number in the list together with the number of times it appears, makes that easier- instead of adding all 50 numbers, you multiply each distinct number by the number of times it occurs then sum those numbers.

If you really do NOT know the meanings of any of those words, as you seem to be saying, you need to talk to your teacher about it.
• Jan 19th 2013, 12:03 PM
gary147
Re: Can someone help me with the task.. very difficult