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3 years ago

Solve for u. U/-1 +-4=-1 U =

Mathematics

1 answer:

kherson [118]3 years ago

3 0

Answer:

U = -3

Step-by-step explanation:

U/-1 +-4=-1

Add 4 to each side

U/-1 +-4+4=-1+4

U / -1 = 3

Multiply each side by -1

U / -1 * -1 = 3* -1

U = -3

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Find the area of the figure below, formed from a triangle and a rectangle, in square centimeters. A figure is formed from a righ

lana [24]

C.44 square centimeters

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3 years ago

How many solutions doe

musickatia [10]

Answer:

Given equation have two solutions.

x = $-\frac{5}{2} and -\frac{8}{3}$

Right option is (D)

Step-by-step explanation:

We have given,

$6x^{2} +40=-31x$

we can rewrite this equation in the form given as:

6x² + 40 + 31x = 0

or 6x² + 31x + 40 = 0

On solving this quadratic equation, we get :

x = $-\frac{5}{2} and -\frac{8}{3}$

That means, given equation have two solutions.

Right option is (D)

8 0

3 years ago

Read 2 more answers

Construct a probability distribution for the data.

lianna [129]

Answer:

X : ___ 0 ____ 1 _____ 2 ______ 3

P(X) : _ 6/15 __ 5/15__ 3/15 ____ 1/15

Step-by-step explanation:

From the data, to produce a probability distribution for the data :

X : number of times blood is drawn ;

P(x) : probability that blood is drawn at X times

Hence, the probability distribution table for the data Given goes thus :

X : ___ 0 ____ 1 _____ 2 ______ 3

P(X) : _ 6/15 __ 5/15__ 3/15 ____ 1/15

Probability that blood is drawn 0 times = 6/15

Probability that blood is drawn 1 time = 5/15

Probability that blood is drawn 2 times = 3/15

Probability that blood is drawn 3 times = 1/15

(6/15 + 5/15 + 3/15 + 1/15) = 1

5 0

3 years ago

SAT scores are normed so that, in any year, the mean of the verbal or math test should be 500 and the standard deviation 100. as

vovangra [49]

Answer:

a) $P(X>625)=P(\frac{X-\mu}{\sigma}>\frac{625-\mu}{\sigma})=P(Z>\frac{625-500}{100})=P(Z>1.25)$

$P(Z>1.25)=1-P(Z$

b) $P(400$

$P(-1$

c) $z=-0.842$

And if we solve for a we got

$a=500 -0.842*100=415.8$

So the value of height that separates the bottom 20% of data from the top 80% is 415.8.

Step-by-step explanation:

Previous concepts

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".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Part a

Let X the random variable that represent the SAT scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(500,100)$

Where $\mu=500$ and $\sigma=100$

We are interested on this probability

$P(X>625)$

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

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

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

$P(X>625)=P(\frac{X-\mu}{\sigma}>\frac{625-\mu}{\sigma})=P(Z>\frac{625-500}{100})=P(Z>1.25)$

And we can find this probability using the complement rule and with the normal standard table or excel:

$P(Z>1.25)=1-P(Z$

Part b

We are interested on this probability

$P(400$

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

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

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

$P(400$

And we can find this probability with this difference:

$P(-1$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(-1$

Part c

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.8$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.2 of the area on the left and 0.8 of the area on the right it's z=-0.842. On this case P(Z<-0.842)=0.2 and P(Z>-0.842)=0.8

If we use condition (b) from previous we have this:

$P(X$

$P(z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=-0.842$

And if we solve for a we got

$a=500 -0.842*100=415.8$

So the value of height that separates the bottom 20% of data from the top 80% is 415.8.

8 0

3 years ago

What is 8 + ¼ ÷ ⅖ using order of operations

Ksivusya [100]

Answer:

exact form: 69/8

mixed number form: 8 5/8

Step-by-step explanation:

1/4 ÷ 2/5 = 5/8 |

5/8+8 = ______|

6 0

3 years ago