All categories

3 years ago

Solve 5h + 2(11 - h) = -5 (Find h. Explain each step please.)

Mathematics

2 answers:

pav-90 [236]3 years ago

7 0

Answer:

h = -9

Step-by-step explanation:

Distribute the 2 to the parentheses:

5h + 2(11 - h) = -5

5h + 22 - 2h = -5

Add like terms:

3h + 22 = -5

3h = -27

h = -9

frosja888 [35]3 years ago

6 0

Answer:

h = -4.5

Step-by-step explanation:

5h + 2(11-h) = -5

5h + 2(11-h)

+h +h

6h + 2 x 11 = -5

6h + 22 = -5

- 22 -22

6h = -27

/6 /6

h = -4.5

I hope this helps, I know the explanation is kinda confusing but I tried my best to explain :))

You might be interested in

SOMEONE PLEASE HELP ME WITH THIS ASAP!

bonufazy [111]

Answer:

y=20

Step-by-step explanation:

0.6(y-10)=6

0.6y-6=6

0.6y=6+6

0.6y=12

y=12/0.6

y=20

the mistake is added 10 to both sides

6 0

3 years ago

What is the answer?<br><br> Y=x-6 and y=2x

Rashid [163]

$\begin{cases}y=x-6\\y=2x\end{cases}\implies~x-6=2x\implies~x=-6$

which means

$y=x-6=y=-6-6=-12$

4 0

3 years ago

Read 2 more answers

23. A certain type of gasoline is supposed to have a mean octane rating of at least 90. Suppose measurements are taken on of 5 r

Nostrana [21]

Answer:

a) $p_v =P(Z$

b) Since $p_v$ we can reject the null hypothesis at the significance level given. So based on this we can commit type of Error I.

Because Type I error " is the rejection of a true null hypothesis".

c) $P(\bar X >90)=1-P(Z$

$1-P(Z$

d) For this case we need a z score that accumulates 0.02 of the area on the right tail and 0.98 on the left tail and this value is z=2.054

And we can use this formula:

$2.054=\frac{90-89}{\frac{0.8}{\sqrt{n}}}$

And if we solve for n we got:

$n = (\frac{2.054 *0.8}{1})^2=2.7 \approx 3$

Step-by-step explanation:

Previous concepts and data given

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

We can calculate the sample mean and deviation with the following formulas:

$\bar X = \frac{\sum_{i=1}^n X_i}{n}$

$s=\sqrt{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}$

$\bar X=88.96$ represent the sample mean

$s=1.011$ represent the sample standard deviation

n=5 represent the sample selected

$\alpha$ significance level

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is less than 90, the system of hypothesis would be:

Null hypothesis: $\mu \geq 90$

Alternative hypothesis: $\mu < 90$

If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

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

$z=\frac{88.96-90}{\frac{0.8}{\sqrt{5}}}=-2.907$

Part a

P-value

First we need to calculate the degrees of freedom given by:

$df=n-1=5-1 = 4$

Then since is a left tailed test the p value would be:

$p_v =P(Z$

Part b

Since $p_v$ we can reject the null hypothesis at the significance level given. So based on this we can commit type of Error I.

Because Type I error " is the rejection of a true null hypothesis".

Part c

We want this probability:

$P(\bar X$

The best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}$

If we apply this formula to our probability we got this:

$P(\bar X >90)=1-P(Z$

$1-P(Z$

Part d

For this case we need a z score that accumulates 0.02 of the area on the right tail and 0.98 on the left tail and this value is z=2.054

And we can use this formula:

$2.054=\frac{90-89}{\frac{0.8}{\sqrt{n}}}$

And if we solve for n we got:

$n = (\frac{2.054 *0.8}{1})^2=2.7 \approx 3$

7 0

3 years ago

Peter randomly draws a card from a deck of 24. The odds in favor of his drawing a spade from the cards are 1:3. What is the prob

oee [108]

Answer:

1 /4

Step-by-step explanation:

Given that :

Let :

P(S) = probability of drawing a spade

Odds in favor of drawing a spade = 1:3 ; this could be interpreted as :

P(drawing a spade)/P(not drawing a spade) = 1:3

P(S) / P(S') = 1/ 3

P(S') = 1 - P(S)

P(S) / (1 - P(S)) = 1 / 3

Cross multiply :

3P(S) = 1 - P(S)

Collect like terms

3P(S) + P(S) = 1

4P(S) = 1

P(S) = 1/4

Hence, probability ratio of drawing a spade P(S) = 1/4

8 0

3 years ago

toothless car wash (the kid next door) can wash 3 cars in one and a half hours. how long will it take to wash 10 cars

katrin2010 [14]

Answer:

5 hours

Step-by-step explanation:

1.5 (hours) / 3(cars) = 0.5 hours per car

0.5 x 10 = 5

6 0

3 years ago