Evaluating the given sequence, it is evident that the next number is twice the number prior to it. Thus, the given is a geometric sequence with first term (a1) equal to 1 and common ratio of 2. The geometric series may be calculated by the equation,
Sn = a1 x (1 - r^n) / (1 - r)
where Sn is the sum of n terms in this case, n = 11.
Substituting the known values,
<span> Sn = 1 x (1 - 2^11) / (1 - 2) = 2047
</span>
Thus, S11 is 2047.
Answer:
250 boys
Step-by-step explanation:
sum the parts of the ratio, 5 + 3 = 8 parts
Divide the total by 8 to find the value of 1 part of the ratio
400 ÷ 8 = 50 , then
number of boys = 5 × 50 = 250
Answer:
M + 3
Step-by-step explanation:
If Jen has 3 more pencils than mike, then you add the amount of pencils to however many mike has which leads to M+3
Answer:
The standard deviation will remain unchanged.
Step-by-step explanation:
Given
Solving (a): The range
This is calculated as:
Where:
So:
Solving (b): The variance
First, we calculate the mean
The variance is calculated as:
So, we have:
![\sigma^2 =\frac{1}{6-1}*[(136 - 135)^2 +(129 - 135)^2 +(141 - 135)^2 +(139 - 135)^2 +(138 - 135)^2 +(127 - 135)^2]](https://tex.z-dn.net/?f=%5Csigma%5E2%20%3D%5Cfrac%7B1%7D%7B6-1%7D%2A%5B%28136%20-%20135%29%5E2%20%2B%28129%20-%20135%29%5E2%20%2B%28141%20-%20135%29%5E2%20%2B%28139%20-%20135%29%5E2%20%2B%28138%20-%20135%29%5E2%20%2B%28127%20-%20135%29%5E2%5D)
![\sigma^2 =\frac{1}{5}*[162]](https://tex.z-dn.net/?f=%5Csigma%5E2%20%3D%5Cfrac%7B1%7D%7B5%7D%2A%5B162%5D)
Solving (c): The standard deviation
This is calculated as:
--- approximately
Solving (d): With the stated condition, the standard deviation will remain unchanged.
Given:
set-up fee 5,500
variable fee 1 per CD.
Cost per CD is $5.50
5.50 - 1= 4.50
5,500 / 4.50 = 1,222 CDs Choice A.
1*1,222 = 1,222
1,222 + 5,500 = 6,722
6,722/1,222 = 5.50
