4. Solve the following equation: 9x - 6 +7x = 16x

Solver for x: 4(1 - x) + 2 x = -3(x + 1)

nydimaria [60]

Answer:

x=7

brainliest?

4 0

3 years ago

Read 2 more answers

An antique store increases all of its prices by $40\%$, and then announces a $25\%$-off-everything sale. What percent of the ori

Mandarinka [93]

Answer:

105%

Step-by-step explanation:

We'll analyse the question one step at a time

Let the original price be x.

Let y be the 40% increase

$y =x + 40\% *x$

Express as decimal

$y =x + 0.40 x$

$y =1.40x$

Let z be the 25% off sale

$z = (1 - 25\%) * y$

Express as decimal

$z = (1 - 0.25) * y$

$z = (0.75) * y$

$z = 0.75y$

Substitute 1.40s for y

$z = 0.75*1.40x$

$z = 1.05x$

Express 1.05 as a fraction

$z = 105\% * x$

<em>The percentage is 105%</em>

5 0

3 years ago

A manufacturer of a new medication on the market for Alzheimer's disease makes a claim that the medication is effective in 65% o

NeX [460]

Answer:

$z=\frac{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309$

$p_v =P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

Step-by-step explanation:

Data given and notation

n=180 represent the random sample taken

X=115 represent the adults with the medication was effective

$\hat p=\frac{115}{180}=0.639$ estimated proportion of adults with the medication was effective

$p_o=0.65$ is the value that we want to test

$\alpha=0.05$ represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that true proportion is less than 0.65.:

Null hypothesis: $p \geq 0.65$

Alternative hypothesis: $p < 0.65$

When we conduct a proportion test we need to use the z statisitc, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.639 -0.65}{\sqrt{\frac{0.65(1-0.65)}{180}}}=-0.309$

Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha=0.05$ . The next step would be calculate the p value for this test.

Since is a left tailed test the p value would be:

$p_v =P(z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults with the medication was effective is not significantly less than 0.65

3 0

3 years ago

Stephen purchased a guitar, which was originally priced at $80 but discounted at 25%. He also had to pay 5% sales tax. What amou

nikdorinn [45]

Discounted by 25% means he paid 75% of the original price:

80 x 0.75 = $60

Now multiply the sale price by 1 + tax rate:

60 x 1.05 = 63

He paid $63 total.

7 0

3 years ago

If you could please help, what is the missing answer?<br><br> Thank you to anyone who helps out!

ICE Princess25 [194]

Answer:

48

Step-by-step explanation:

let s be the snowman, g be the girl, and t be the christmas tree

2s+g=24

2t+2ts=132

3t+2g=26

subtract 2 times the first equation from the third one to get

3t-4s=-22

from the second equation we can deduce

2t(1+s)=132

t(1+s)=66

t=66/(1+s)

Substitute:

3(66)/(1+s)-4s=-22

3(66)/(1+s)=4s-22

3(66)=(4s-22)(1+s)

3(66)=-18s+4s^2-22

4s^2-18s-220=0

using the quadratic formula, we get s = 10, s = -5.5.

2(10)+g=24

g=4

2t(1+10)=132

2t=12

t=6

So 2s+t*g= 20+6*4=48

you would get a different solution for the negative s, but since snowmen cannot be negative, 48 is the answe.r

8 0

3 years ago

4. Solve the following equation: 9x - 6 +7x = 16x - 6