Help me please people

Your friend invested $500 in his shop to start off, and makes a $20 profit every week afterwards. Find the minimum number of wee

Jet001 [13]

It will take 45 weeks.25 weeks to gain back the 500 dollor he spent and 20 to make 400 dollor from it

5 0

2 years ago

Anyone know? I need help it’d be cool if someone gave the answer

photoshop1234 [79]

Answer: 19 units

Step-by-step explanation:

Count from A down then the left until you reach B.

8 0

3 years ago

A study of the number of business lunches that executives in the insurance and banking industries claim as deductible expenses p

gizmo_the_mogwai [7]

Answer:

$t=\frac{9.1-8}{\sqrt{\frac{(1.9)^2}{40}+\frac{(2.1)^2}{50}}}}=2.604$

$p_v =2*P(t_{(88)}>2.604)=0.0108$

So the p value is a very low value and using any significance level for given $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the two means are significantly different at 5%

Step-by-step explanation:

Data given and notation

$\bar X_{1}=9.1$ represent the mean for the sample 1

$\bar X_{2}=8$ represent the mean for the sample 2

$s_{1}=1.9$ represent the sample standard deviation for the sample 1

$s_{2}=2.1$ represent the sample standard deviation for the sample 2

$n_{1}=40$ sample size for the group 1

$n_{2}=50$ sample size for the group 2

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean are different , the system of hypothesis would be:

Null hypothesis: $\mu_{1} = \mu_{2}$

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

If we analyze the size for the samples both are higher than 30 and the population deviations are not given, so for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{\bar X_{1}-\bar X_{2}}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

t-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

We can replace in formula (1) the results obtained like this:

$t=\frac{9.1-8}{\sqrt{\frac{(1.9)^2}{40}+\frac{(2.1)^2}{50}}}}=2.604$

Statistical decision

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

$df=n_{1}+n_{2}-2=40+50-2=88$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{(88)}>2.604)=0.0108$

So the p value is a very low value and using any significance level for given $\alpha=0.05$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and there is enough evidence to conclude that the two means are significantly different at 5%

3 0

2 years ago

The volume of this cone is 2,279.64 cubic millimeters. What is the height of this cone?

masha68 [24]

Step-by-step explanation:

you've been doing so much for your life

3 0

3 years ago

a survey of 504 citizens found that 378 of them favor a new bill introduced by the city. We want to find a 95% confidence interv

Viefleur [7K]

The lower limit of the interval is 0.712 if the survey of 504 citizens found that 378 of them favor a new bill introduced by the city.

<h3>What is a confidence interval?</h3>

It is defined as the sampling distribution following an approximately normal distribution for known standard deviation.

We have:

A survey of 504 citizens found that 378 of them favor a new bill introduced by the city.

Sample proportion = p = 378/504 = 0.75

q = 1 - p = 1 - 0.75 = 0.25

$\rm SD = \sqrt{\dfrac{pq}{n}}$

$\rm SD = \sqrt{\dfrac{0.75\times0.25}{504}}$

SD = 0.01928

For 95% confidence interval Z value = 1.96

Lower limit = 0.75 - 1.96(0.01928)

= 0.712

Thus, the lower limit of the interval is 0.712 if the survey of 504 citizens found that 378 of them favor a new bill introduced by the city.

Learn more about the confidence interval here:

brainly.com/question/6654139

#SPJ1

3 0

2 years ago