Posted by **Joan** on Sunday, January 27, 2008 at 6:48pm.

-A set of seven scores has a mean of 10. If one of the scores is changed from X=15 to X=1, what will be the new value for the new mean?

-A sample of n=8 scores has a mean of M=12. One new score is added to the same and the new mean is found to be M=13. What is the vaule of the new score?

What steps do I follow to figure out these types of problems? I don't quite understand how the book is explaining it.

- statistics -
**drwls**, Sunday, January 27, 2008 at 7:04pm
If a set of seven numbers has a mean of 10, then the sum of the ten numbers must be 70. If you raise one of thme from 1 to 15, than the total becomes 84. Divide that by 7 for the new mean value.

Use a similar approach for the second question. The total for the first 8 numbers is 8x12 = 96. When a ninth number is added, the total becomes 9x13 = 117. How much did the thirteenth number add to the total?

## Answer This Question

## Related Questions

- Stats - A sample of n=9 scores has a mean of M=20. One of the scores is changed...
- Statistics - For a population with a mean of (mew) = 50 and a standard deviation...
- statistics - A population of N=8 scores has a mean of µ = 20. If one score is ...
- statistics - A population of N=8 scores has a mean of µ = 20. If one score is ...
- Math - I need help with this these two problem PLEASE!!! For a population with ...
- statistics - A population of N=8 scores has a mean of M =20. If one score is ...
- probability and statistics - a population forms a normal distribution with a ...
- algebra - tenequal scores have a mean of 30. if one score is doubled, and the ...
- statistics - A sample of n = 20 scores has a mean of M = 6. If one new person ...
- Statistics - One sample of n=20 scores has a mean of M=50. A second sample of n=...

More Related Questions