Mean = (89 + 90 + 87 + 95 + 86 + 81 + 102 + 105 + 83 + 88 + 91 + 79)/12 = 1,076/12 = 89.67
a.) 95% C.I. = 89.67 + or - 1.96(0.23) = 89.67 + or - 0.4508 = 89.22 to 90.12
b.) 99% C. I = 89.67 + or - 2.575(0.23) = 89.67 + or - 0.5923 = 89.08 to 90.26
Answer:

Step-by-step explanation:
<u>Geometric Sequences</u>
The geometric sequence is given as:

Where n is the number of the term, n≥1, and r is the common ratio.
The sum of n terms of the geometric sequence is given by:

We are given: S3=252, a1=192, thus substuting:

Dividing by 12:

Recall that:

Substituting:

Simplifying:

Rearranging:

16r^2+16r-5=0
Rewriting:

Factoring:


Solving:

Both solutions are valid
7.2 take 1.2 and multiply by 6
Answer:
300 seconds
Step-by-step explanation:
First, you have to know how much half a minute is. Half a minute is 30 seconds.
Second, you multiply 30 by 10 because he answered 10 questions.
30 * 10 = 300
So your answer is 300 seconds
Lastly, have a great day! :)
Answer:
In the document, Westing names the sixteen heirs present as his “nieces and nephews” and says that tomorrow his ashes “will be scattered to the four winds.” He then asserts that his life has been taken by one of his heirs, and he promises that the heir who finds something will receive the inheritance
Step-by-step explanation: