If you randomly purchase one item, the probability it will last longer than 9 years is; 11.12%
<h3>How to find the probability from z-score?</h3>
The formula for Z-score is;
z = (x' - µ)/σ
where;
x' = sample mean
µ = population mean
σ = standard deviation
Thus;
z = (9 - 7.9)/0.9
z = 1.22
From online p-value from z-score calculator, we have;
probability = 0.1112 = 11.12%
Read more about Z-score probability at; brainly.com/question/25638875
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This is what we have:
![\frac{x}{5} =a](https://tex.z-dn.net/?f=%20%5Cfrac%7Bx%7D%7B5%7D%20%3Da)
what we want is for x to "stand alone": for this, we need to get rid of this 5. we can do this by multiplying both sides of the equation by 5:
![\frac{x*5}{5} =a*5](https://tex.z-dn.net/?f=%20%5Cfrac%7Bx%2A5%7D%7B5%7D%20%3Da%2A5)
if we both divide and mupliply the first numebr by 5, it just means 1, so we can skip it:
Area is length x width
the answer is 7
8 x 7 = 56
so the one u clicked is right haha
The given sequence is
a₁, a₂, ...,
![a_{n}](https://tex.z-dn.net/?f=%20a_%7Bn%7D%20)
Because the given sequence is an arithmetic progression (AP), the equation satisfied is
![a_{n}=a_{1}+(n-1)d](https://tex.z-dn.net/?f=%20a_%7Bn%7D%3Da_%7B1%7D%2B%28n-1%29d%20)
where
d = the common difference.
The common difference may be determined as
d = a₂ - a₁
The common difference is the difference between successive terms, therefore
d = a₃ - a₂ = a₄ - a₃, and so on..
The sum of the first n terms is
![S_{n}= \frac{n}{2} (a_{1}+a_{n})](https://tex.z-dn.net/?f=S_%7Bn%7D%3D%20%5Cfrac%7Bn%7D%7B2%7D%20%28a_%7B1%7D%2Ba_%7Bn%7D%29)
Example:
For the arithmetic sequence
1,3,5, ...,
the common difference is d= 3 - 1 = 2.
The n-th term is
![a_{n}=1+2(n-1)](https://tex.z-dn.net/?f=a_%7Bn%7D%3D1%2B2%28n-1%29)
For example, the 10-term is
a₁₀ = 1 + (10-1)*2 = 19
Th sum of th first 10 terms is
S₁₀ = (10/2)*(1 + 19) = 100
Answer: Yes. The cookies are $ .75 each. The total cost is proportional to the number of cookies purchased.
T = $.75 × c
Step-by-step explanation: