Compute: (3.5· 2/7 − 2/3 )÷16

Someone please help math question?ASAP

natali 33 [55]

A I am pretty sure. I apologize if I am incorrect.

3 0

2 years ago

Solve for x. x -5 x 7 ÷(8 - 9)<br> help lease

Colt1911 [192]

The answer is 35 !!!!!!!!!!!!!

6 0

2 years ago

Read 2 more answers

Giving brainliestttyttttt

-Dominant- [34]

Answer:

C

Step-by-step explanation:

Because its right

4 0

1 year 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

Who had a head start, and how many miles was the head start? Rita had a 28-mile head start. Roger had a 26-mile head start. Roge

serg [7]

Complete question is;

Roger and Rita each drive at a constant speed between Phoenix and San Diego. Each driver’s distance for the same section of the trip is displayed below. Who had a head start, and how many miles was the head start?

A) Rita had a 28-mile head start.

B) Roger had a 26-mile head start.

C) Roger had a 25-mile head start.

D) Rita had a 22-mile head start.

Answer:

A) Rita had a 28-mile head start.

Step-by-step explanation:

Let's assume that Roger travelled a distance of 60 miles

And that;

Rita travelled a distance of 32 miles

We are told that they travelled between Phoenix and San Diego.

Thus, it means that if they have different distances but covered same section of the trip, it means the one with higher distance started before the section of the trip.

Thus, it means that Rita had a head start of Roger since she covered only 32 miles.

Thus;

Rita had a head start of; 60 - 32 = 28 miles

4 0

2 years ago