Ask question

Ask question

All categories

2 years ago

13

The seats at a local baseball stadium are arranged so that each row has 5 more seat than the row in front of it. If there are fo

ur seats in the first row, how many total seats are in the first 24 rows

1 answer:

ohaa [14]2 years ago

4 0

You would do an arithmetic sequence
use A1 +(n-1)d to calculate number of seats in the last row

An = 4+(24-1)5
An = 4 + (23)(5)
An = 4 + 115
An = 119 seats in the last row

now use a sum sequence to find total number of seats

Sn = n(a1 + an)/2
Sn = 24(4+119)/2
Sn = 24(123) /2
Sn = 1476 total seats

You might be interested in

4. You want to know if there's an association between college students' spring break destinations and what year they're in. You

Pachacha [2.7K]

Answer:

$\chi^2 =27.356$

$p_v = P(\chi^2_{9} >27.356)=0.00122$

And we can find the p value using the following excel code:

"=1-CHISQ.DIST(27.356,9,TRUE)"

Since the p value is lower than the significance level assumed 0.05 we can reject the null hypothesis at 5% of significance, and we can conclude that we have association between the two variables analyzed.

Step-by-step explanation:

A chi-square goodness of fit test "determines if a sample data matches a population".

A chi-square test for independence "compares two variables in a contingency table to see if they are related. In a more general sense, it tests to see whether distributions of categorical variables differ from each another".

Assume the following dataset:

Amusement Parks Mexico Home Other Total

Freshman 23 21 43 21 108

Sophomore 34 23 14 26 97

Junior 25 30 23 26 104

Senior 27 33 17 19 96

Total 109 107 97 92 405

We need to conduct a chi square test in order to check the following hypothesis:

H0: There is independence between the two random variables

H1: There is dependence between the two variables

The level os significance assumed for this case is $\alpha=0.05$

The statistic to check the hypothesis is given by:

$\chi^2 =\sum_{i=1}^n \frac{(O_i -E_i)^2}{E_i}$

The table given represent the observed values, we just need to calculate the expected values with the following formula $E_i = \frac{total col * total row}{grand total}$

And the calculations are given by:

$E_{1} =\frac{109*108}{405}=29.07$

$E_{2} =\frac{107*108}{405}=28.53$

$E_{3} =\frac{97*108}{405}=25.87$

$E_{4} =\frac{92*108}{405}=24.53$

$E_{5} =\frac{109*97}{405}=26.11$

$E_{6} =\frac{107*97}{405}=25.63$

$E_{7} =\frac{97*97}{405}=23.23$

$E_{8} =\frac{92*97}{405}=22.03$

$E_{9} =\frac{109*104}{405}=27.99$

$E_{10} =\frac{107*104}{405}=27.48$

$E_{11} =\frac{97*104}{405}=24.91$

$E_{12} =\frac{92*104}{405}=23.62$

$E_{13} =\frac{109*96}{405}=25.84$

$E_{14} =\frac{107*96}{405}=25.36$

$E_{15} =\frac{97*96}{405}=22.99$

$E_{16} =\frac{92*96}{405}=21.81$

And the expected values are given by:

Amusement Parks Mexico Home Other Total

Freshman 29.07 28.53 25.87 24.53 108

Sophomore 26.11 25.63 23.23 22.03 97

Junior 27.99 27.48 24.91 23.62 104

Senior 25.84 25.36 22.99 21.81 96

Total 109 107 97 92 405

And now we can calculate the statistic:

$\chi^2 =27.356$

Now we can calculate the degrees of freedom for the statistic given by:

$df=(rows-1)(cols-1)=(4-1)(4-1)=9$

And we can calculate the p value given by:

$p_v = P(\chi^2_{9} >27.356)=0.00122$

And we can find the p value using the following excel code:

"=1-CHISQ.DIST(27.356,9,TRUE)"

Since the p value is lower than the significance level assumed 0.05 we can reject the null hypothesis at 5% of significance, and we can conclude that we have association between the two variables analyzed.

7 0

2 years ago

Please help 1. another term for adding money to an account is

zzz [600]

<span>Payment. While payment is the sum of money paid in exchange for something either goods and services; the money can be credited (or added) into an account directly without making direct payment. We can also credit our account which is also payments. The most efficient way of building a savings is having a set minimum or percentage for saving whichever is greater. Sometimes we may need to save more than our "set minimum" especially when we earn more. The higher we earn the more our set minimum pales in comparison to what we ought to save. On the other hand if we have a set percentage it would also need to be raised higher when we earn more, but saving whichever is greater ensures that we make the best and most efficient savings decision at any period in time.</span>

5 0

3 years ago

Read 2 more answers

Can someone please help me?

user100 [1]

Recognize and represent proportional relationships between quantities. Decide whether two quantities are in a proportional relationship, e.g., by testing for equivalent ratios in a table or graphing on a coordinate plane and observing whether the graph is a straight line through the origin.

3 0

2 years ago

Read 2 more answers

What is equivalent to 5^3•5^4

mafiozo [28]

Answer:

${5}^{7}$

Step-by-step explanation:

$5^3•5^4 = {5}^{3 + 4} = \purple{ \bold{ {5}^{7} }}$

8 0

2 years ago

9 < 11, so 9(5) < 11(5) true or false?

Zolol [24]

It is true since you’re multiplying the same number on both the sides

7 0

2 years ago