Help! Stats! A sample size of 7 (n=7) has a mean of M=9. One of the sample scores is changed from x=19 to x=5. What is the value for the new sample mean? How can I do this without ALL of the variables?

Question

Help!  Stats! A sample size of 7 (n=7) has a mean of M=9.  One of the sample scores is changed from x=19 to x=5.  What is the value for the new sample mean?  How can I do this without ALL of the variables?

anonymous · Answer

what. how can the mean possibly increase if one of the values decreases? For example, if the values were 1,2,4,8,14,15,19 (mean 9) and you change the 19 to 5, the new mean would be 7. If a value is decreased, then the mean will always decrease

campbell_st · Answer

well look at it this way

Mean = sum of the score/number of scores

so

Sum of the score  = mean x number of scores

Sum = 9 x 7

so the sum of the scores is 63

now if 19 is removed subtract it

63 - 19 = 44

if 5 is added in place of 19 

the sum of the scores is

44 + 5 = 49

so the new mean is 

Mean = 49/7

just calculate it.

anonymous · Answer

i was just wondering cause in your previous post you got a higher mean than the original after one of the sample numbers was decreased