The table on the right gives the annual income for eight families, in thousands of dollars. Find the number of standard deviations family A's income is from the mean.

Family: A B C D E F G H
Income: 50 52 50 49 48 49 46 48

I believe I figured out the mean for the total income is 49 and the standard deviation (rounded) is 1.01. My book does not show me how to find the standard deviation for one particular section of information.

Any help on how to solve this would be appreciated.

Question

The table on the right gives the annual income for eight families, in thousands of dollars.  Find the number of standard deviations family A's income is from the mean.

Family:   A     B    C   D    E    F    G    H
Income: 50   52  50  49  48  49  46  48

I believe I figured out the mean for the total income is 49 and the standard deviation (rounded) is 1.01.  My book does not show me how to find the standard deviation for one particular section of information.

Any help on how to solve this would be appreciated.

amistre64 · Answer

familyA - mean
--------------
      std dev

amistre64 · Answer

how many standard deviations can you fit between the mean and family A?

if you used the standard deviation value is a unit of measure;  how many of them does it take to get from the mean to familyA?

amistre64 · Answer

and the sd is:  1.66 for the population,  or if this is a sample 1.77

anonymous · Answer

Oh my goodness.  I did not know it was as simple as that.  Thank you so very much.  That helps immensely.