Calculate for the mean/ average of the given numbers:
μ = (1 + 2 + 3 + 4 + 5) / 5 = 3
Then, we calculate for the summation of the squares of differences of these numbers from the mean, S
S = (1 - 3)² + (2 - 3)² + (3 - 3)² + (4 - 3)² + (5 - 3)²
S = 10
Divide this summation by the number of items and take the square root of the result to get the standard deviation.
SD = sqrt (10 / 5) = sqrt 2
SD = 1.41
Thus, the standard deviation of the given is equal to 1.41.
X = Dimes Y = Nickels
x + y = 175
.10x + .05y = 13.30
Answer:
Since there is no value of x that will ever make this a true statement, the solution to the equation above is “no solution”. Be careful that you do not confuse the solution x = 0 with “no solution”. The solution x = 0 means that the value 0 satisfies the equation, so there is a solution.
Step-by-step explanation:
The pattern is formed a geometric sequence
The nth term of the sequence is 
Step-by-step explanation:
The formula of the nth term of a geometric sequence is:
, where
- a is the first term
- r is the common ratio between the consecutive terms
∵ The pattern is 3 , 9 , 27 , 81 , 243
∵ 9 ÷ 3 = 3
∵ 27 ÷ 9 = 3
∵ 81 ÷ 27 = 3
∵ 243 ÷ 81 = 3
- There is a common ratio 3 between each two consecutive terms
∴ The pattern is formed a geometric sequence
∵ The first term is 3
∴ a = 3
∵ The common ratio is 3
∴ r = 3
- To find the nth term substitute a and r in the formula above
∵
∴
- Remember we add the powers of the same base with multiplication
∵ 3 ×
= 
∴ 3 ×
= 
∴ 
∴ The nth term of the sequence is
Learn more:
You can learn more about the sequences in brainly.com/question/1522572
#LearnwithBrainly
So, since averages are defined as:

So, since P are the total number of elements and P_k is the P_kth student. This is saying if we sum over each student's score and divide it by the number of students, we should get P, which is true.
So, using that logic, the other class can be represented as:

We can take both of these equations and multiply them by N:


So, if we want to find the average of this we should add both our equations then divide by P+N, which is the number of all the students.

To make this simpler we can replace our LHS with 86, since that's the average of both classes combined.

Simplified we would have P/N=3/8.