I need help... please. I literally suck at math

Each person in a group of college students was identified by graduating year and asked when he or she preferred taking classes:

swat32

Answer:

0.615

Step-by-step explanation:

The frequency table is attached below.

We have to calculate, the probability that the student preferred morning classes given he or she is a junior.

i.e $P(\text{Morning }|\text{ Junior})$

We know that,

$P(A\ |\ B)=\dfrac{P(A\ \cap\ B)}{P(B)}$

So,

$P(\text{Morning }|\text{ Junior})=\dfrac{P(\text{Morning }\cap \text{ Junior})}{P(\text{Junior})}$

Putting the values from the table,

$\dfrac{P(\text{Morning }\cap \text{ Junior})}{P(\text{Junior})}=\dfrac{\frac{16}{143}}{\frac{26}{143}}=\dfrac{16}{26}=0.615$

3 0

2 years ago

An equation with a graph that is a straight line is called

Alinara [238K]

The answer is called a linear equation :))

7 0

2 years ago

One liter of paint covers 100 square feet. How many gallons of paint does it take to cover a room whose walls have an area of 80

Finger [1]

Its 3200 square feet so 32 gallons

5 0

3 years ago

g A certain financial services company uses surveys of adults age 18 and older to determine if personal financial fitness is cha

leva [86]

Answer:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

$z=\frac{0.410-0.35}{\sqrt{0.385(1-0.385)(\frac{1}{1000}+\frac{1}{700})}}=2.502$

$p_v =2*P(Z>2.502)= 0.0123$

Comparing the p value with the significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to to reject the null hypothesis, and we can say that the proportion analyzed is significantly different between the two groups at 5% of significance.

Step-by-step explanation:

Data given and notation

$X_{1}=410$ represent the number of people indicating that their financial security was more than fair for the recent year

$X_{2}=245$ represent the number of people indicating that their financial security was more than fair for the year before

$n_{1}=1000$ sample 1 selected

$n_{2}=700$ sample 2 selected

$p_{1}=\frac{410}{1000}=0.410$ represent the proportion estimated of indicating that their financial security was more than fair this year

$p_{2}=\frac{245}{700}=0.35$ represent the proportion estimated of indicating that their financial security was more than fair the year before

$\hat p$ represent the pooled estimate of p

z would represent the statistic (variable of interest)

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

$\alpha$ significance level given

Concepts and formulas to use

We need to conduct a hypothesis in order to check if is there is a difference between the two proportions, the system of hypothesis would be:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{410+245}{1000+700}=0.385$

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.410-0.35}{\sqrt{0.385(1-0.385)(\frac{1}{1000}+\frac{1}{700})}}=2.502$

Statistical decision

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

$p_v =2*P(Z>2.502)= 0.0123$

Comparing the p value with the significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to to reject the null hypothesis, and we can say that the proportion analyzed is significantly different between the two groups at 5% of significance.

7 0

2 years ago

rewrite the polynomial 2y^2+ 6y^3-11-17y^4+8y^5 in the standard form also find its degree and coefficient of y^4

OleMash [197]

Answer:

The standard form is 8 y ⁵ - 17 y⁴ + 6 y³ +2 y² - 11

The degree of given polynomial is '5'

the co-efficient of y⁴ is '-17'

Step-by-step explanation:

Given standard form 2 y²+ 6 y³-11-17 y⁴+8 y⁵

The form ax² + b x + c is called the standard form of the quadratic expression of 'x'.This is second degree standard form of polynomial.

The form ax⁵ + b x⁴ + c x³ +d x² +ex +f is called the standard form of the quadratic expression of 'x'.This is fifth degree standard form of polynomial

now Given polynomial is 2 y²+ 6 y³-11-17 y⁴+8 y⁵

The standard form is

8 y ⁵ - 17 y⁴ + 6 y³ +2 y² - 11

Conclusion:-

The degree of given polynomial is '5'

The co-efficient of y⁴ is '-17'

5 0

3 years ago