1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
bogdanovich [222]
3 years ago
12

The nth term of a sequence is 2n^2 + 4n - 1 Work out the 10th term of the sequence

Mathematics
1 answer:
Svetlanka [38]3 years ago
4 0

Answer:

a₁₀ = 239

Step-by-step explanation:

Substitute n = 10 into the nth term rule , that is

a₁₀ = 2(10)² + 4(10) - 1

    = 2(100) + 40 - 1

    = 200 + 39

   = 239

You might be interested in
How do you graph for the function Y= -x+1
Tanzania [10]
-x = -1. Anything “X” equals to the number One. So do Y = -1 + 1.
5 0
3 years ago
Read 2 more answers
Leo wants to paint a mural that covers a wall with an area of 600 square feet. The height of the wall is 2/3 of its length. What
Gre4nikov [31]

Answer: attached

Step-by-step explanation:

4 0
3 years ago
The national mean annual salary for a school administrator is $90,00 a year (The Cincinnati Enquirer, April 7, 2012). A school o
timurjin [86]

Answer:

a) Null hypothesis:\mu = 90000  

Alternative hypothesis:\mu \neq 90000  

b) p_v =2*P(t_{(24)}  

c) If we compare the p value and the significance level given \alpha=0.05 we see that p_v so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean for the salary differs from 9000 at 5% of significance.

Step-by-step explanation:

1) Data given and notation  

77600 ,76000 ,90700 ,97200 ,90700 ,101800 ,78700 ,81300 ,84200 ,97600 ,

77500 ,75700 ,89400 ,84300 ,78700 ,84600 ,87700 ,103400 ,83800 ,101300

94700 ,69200 ,95400 ,61500 ,68800

We can calculate the sample mean and deviation with the following formulas:

\bar X =\frac{\sum_{i=1}^n X_i}{n}

s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}

The values obtained are:

\bar X=85272 represent the mean annual salary for the sample  

s=11039.23 represent the sample standard deviation for the sample  

n=25 sample size  

\mu_o =90000 represent the value that we want to test

\alpha=0.05 represent the significance level for the hypothesis test.  

t would represent the statistic (variable of interest)  

p_v represent the p value for the test (variable of interest)  

Part a: State the null and alternative hypotheses.  

We need to conduct a hypothesis in order to check if the mean salary differs from 90000, the system of hypothesis would be:  

Null hypothesis:\mu = 90000  

Alternative hypothesis:\mu \neq 90000  

If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:  

t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}  (1)  

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".  

Part b: Calculate the statistic

We can replace in formula (1) the info given like this:  

t=\frac{85272-90000}{\frac{11039.23}{\sqrt{25}}}=-2.141    

P-value

The first step is calculate the degrees of freedom, on this case:  

df=n-1=25-1=24  

Since is a two sided test the p value would be:  

p_v =2*P(t_{(24)}  

Part c: Conclusion  

If we compare the p value and the significance level given \alpha=0.05 we see that p_v so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean for the salary differs from 9000 at 5% of significance.

6 0
3 years ago
Can someone please help me with the second question….will give brainliest :(
den301095 [7]

Answer:

its 3.

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
The difference of 22 and a number is -8<br><br> A.14<br> B.30<br> C.-30<br> D.-14
DIA [1.3K]

Answer:

B. 30

Step-by-step explanation:

the equation looks like 22 - x = -8  and 22 - 30 is negative 8

3 0
3 years ago
Read 2 more answers
Other questions:
  • In the Department of Natural Sciences, 14 faculty members have a PhD, and 30 faculty
    6·1 answer
  • Which figures can be precisely defined by using only undefined terms
    11·1 answer
  • Use the table for each problem to find the given limits.
    7·1 answer
  • If sin α + cos α = 1.2, find sin α · cos α THANKS! (:
    9·1 answer
  • If 270 is 60% of the total was is the full total?
    11·2 answers
  • What is -2(-6+1)=-2x-2(-5-x)
    10·1 answer
  • Solve the equation 3/4 X+-2X=-1/4+1/2X+5​
    8·1 answer
  • Which equation is represented by the table of values below
    9·1 answer
  • George weeded 1/4 of the garden, and summer weeded, some too. When they were finished, 2/5 of the garden still needed to be weed
    7·1 answer
  • Help! I don't know if this is correct.
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!