Please help ASAP!!! 42 points and will mark brainliest for RIGHT answer!!!

Simplify the following expression (x+3)(x+5)

Tju [1.3M]

Answer:

2x+8

Step-by-step explanation:

Here, you have to find the similar sides. x and x are both the same thing, while 3 and 5 are both integers (whole numbers).

You add the similar sides together, then that is your answer.

x + x= 2x, and 3+5= 8.

Note: Just because I said that x and x are the same doesn't mean that you can just add random numbers together in other questions.

3 0

3 years ago

The following 5 questions are based on this information: An economist claims that average weekly food expenditure of households

liq [111]

Answer:

Null hypothesis: $\mu_{1}-\mu_{0}\leq 0$

Alternative hypothesis: $\mu_{1}-\mu_{2}>0$

$SE=\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}=2.705$

b) 2.70

$t=\frac{(164-159)-0}{\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}}=1.850$

b. 1.85

$p_v =P(Z>1.85)=0.032$

b. 0.03

a. We can reject H(0) in favor of H(a)

Step-by-step explanation:

Data given and notation

$\bar X_{1}=164$ represent the mean for the sample 1

$\bar X_{2}=159$ represent the mean for the sample 2

$\sigma_{1}=12.5$ represent the population standard deviation for the sample 1

$s_{2}=9.25$ represent the population standard deviation for the sample B2

$n_{1}=35$ sample size selected 1

$n_{2}=30$ sample size selected 2

$\alpha=0.05$ 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)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the expenditure of households in City 1 is more than that of households in City 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{0}\leq 0$

Alternative hypothesis: $\mu_{1}-\mu_{2}>0$

We know the population deviations, so for this case is better apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{1}-\bar X_{2})-0}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (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".

Standard error

The standard error on this case is given by:

$SE=\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}$

Replacing the values that we have we got:

$SE=\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}=2.705$

b. 2.70

Calculate the statistic

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

$t=\frac{(164-159)-0}{\sqrt{\frac{12.5^2}{35}+\frac{9.25^2}{30}}}=1.850$

P-value

Since is a one side right tailed test the p value would be:

$p_v =P(Z>1.85)=0.032$

b. 0.03

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.

a. We can reject H(0) in favor of H(a)

4 0

3 years ago

Of all of the individuals who develop a certain rash, suppose the mean recovery time for individuals who do not use any form of

VashaNatasha [74]

Answer:

z(s) is in the rejection region. We reject H₀. We dont have enought evidence to support that the cream has effect over the recovery time

Step-by-step explanation:

Sample information:

Size n = 100

mean x = 28,5

Population information

μ₀ = 30

Standard deviation σ = 8

Test Hypothesis

Null Hypothesis H₀ x = μ₀

Alternative Hypothesis Hₐ x < μ₀

We assume CI = 95 % then α = 5 % α = 0,05

As the alternative hypothesis suggest we should develop a one tail-test on the left ( we need to find out if the cream have any effect on the rash), effects on the rash could be measured as days of recovery

A z(c) for 0,05 from z-table is: z(c) = - 1,64

z(s) = ( x - μ₀ ) / σ/√n

z(s) = ( 28,5 - 30 ) / 8/√100

z(s) = - 1,5 * 10 / 8

z(s) = - 1,875

Comparing z(s) and z(c)

|z(s)| < |z(c)| 1,875 > 1,64

z(s) is in the rejection region. We reject H₀. We dont have enought evidence to support that the cream has effect over the recovery time

3 0

3 years ago

Drag each tile to the correct box.

ivolga24 [154]

Answer:

1 and 27, 12 and 33, 6 and 24, 36 and 81, 12 and 96.

Step-by-step explanation:

GCF of 36 and 81: 9

GCF of 1 and 27: 1

GCF of 12 and 33: 3

GCF of 12 and 96: 12

GCF of 6 and 24: 6

3 0

3 years ago

2 0,484,163 expanded form

Oksi-84 [34.3K]

20,000,000+400,000+80,000+4,000+100+60+3

4 0

3 years ago