The manager of a warehouse would like to know how many errors are made when a product's serial number is read by a bar-code reader. Six samples are collected of the number of scanning errors: 36, 14, 21, 39, 11, and 2 errors, per 1,000
scans each
Just to be sure, the manager has six more samples taken:
33, 45, 34, 17, 1, and 29 errors, per 1,000 scans each
How do the mean and standard deviation change, based on all 12 samples?

14.625

Step-by-step explanation:

As per the situation the solution of mean and standard deviation change, based on all 12 samples is represented below:-

Mean of all 12 samples is shown below:-

So, the Mean = 23.5

and now,

The  Standard deviation of all 12 samples is shown below:-

= 14.625

Therefore, we used the above equation to reach  the answer.

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.