Translate into an algebraic expressions: a x is increased by 50% and decreased by 30% . What is the result?

Answer:

The  probability of a bulb lasting for at most 552 hours.

P(x>552)  = 0.0515

Step-by-step explanation:

Step(i):-

Given mean of the life time of a bulb = 510 hours

Standard deviation of the lifetime of a bulb = 25 hours

Let 'X' be the random variable in normal distribution

Let 'x' = 552

[tex]Z = \frac{x-mean}{S.D} = \frac{552-510}{25} =1.628[/tex]

Step(ii):-

The  probability of a bulb lasting for at most 552 hours.

P(x>552) = P(Z>1.63)

               = 1- P( Z< 1.63)

               =  1 - ( 0.5 + A(1.63)

              =   1- 0.5 - A(1.63)

              =   0.5 -A(1.63)

              =   0.5 -0.4485

             =  0.0515

Conclusion:-

The  probability of a bulb lasting for at most 552 hours.

P(x>552)  = 0.0515

Answer:

c=21

Step-by-step explanation:

[tex]3(c-5)=48\\3c-15=48\\3c=48+15\\3c=63\\c=63/3\\c=21[/tex]

Hope this helps,

plx give brainliest

Answer:

c=21

Step-by-step explanation:

3(c−5)=48

Divide both sides by 3.

c-5=48/3

Divide 48 by 3 to get 16.

c−5=16

Add 5 to both sides.

c=16+5

Add 16 and 5 to get 21.

c=21

Slope is the change in y over the change in x

Slope = (1-0) /( -3 - -4)

Slope = 1/1

Slope = 1

Answer:

The probability that a piece of pottery will be finished within 95 minutes is 0.0823.

Step-by-step explanation:

We are given that the time of wheel throwing and the time of firing are normally distributed variables with means of 40 minutes and 60 minutes and standard deviations of 2 minutes and 3 minutes, respectively.

Let X = time of wheel throwing

So, X ~ Normal([tex]\mu_x=40 \text{ min}, \sigma^{2}_x = 2^{2} \text{ min}[/tex])

where, [tex]\mu_x[/tex] = mean time of wheel throwing

            [tex]\sigma_x[/tex] = standard deviation of wheel throwing

Similarly, let Y = time of firing

So, Y ~ Normal([tex]\mu_y=60 \text{ min}, \sigma^{2}_y = 3^{2} \text{ min}[/tex])

where, [tex]\mu_y[/tex] = mean time of firing

            [tex]\sigma_y[/tex] = standard deviation of firing

Now, let P = a random variable that involves both the steps of throwing and firing of wheel

SO, P = X + Y

Mean of P, E(P) = E(X) + E(Y)

                   [tex]\mu_p=\mu_x+\mu_y[/tex]

                        = 40 + 60 = 100 minutes

Variance of P, V(P) = V(X + Y)

                               = V(X) + V(Y) - Cov(X,Y)

                               = [tex]2^{2} +3^{2}-0[/tex]  

{Here Cov(X,Y) = 0 because the time of wheel throwing and time of firing are independent random variables}

SO, V(P) = 4 + 9 = 13

which means Standard deviation(P), [tex]\sigma_p[/tex] = [tex]\sqrt{13}[/tex]

Hence, P ~ Normal([tex]\mu_p=100, \sigma_p^{2} = (\sqrt{13})^{2}[/tex])

The z-score probability distribution of the normal distribution is given by;

                           Z  =  [tex]\frac{P- \mu_p}{\sigma_p}[/tex]  ~ N(0,1)

where, [tex]\mu_p[/tex] = mean time in making pottery = 100 minutes

           [tex]\sigma_p[/tex] = standard deviation = [tex]\sqrt{13}[/tex] minutes

Now, the probability that a piece of pottery will be finished within 95 minutes is given by = P(P [tex]\leq[/tex] 95 min)

     P(P [tex]\leq[/tex] 95 min) = P( [tex]\frac{P- \mu_p}{\sigma_p}[/tex] [tex]\leq[/tex] [tex]\frac{95-100}{\sqrt{13} }[/tex] ) = P(Z [tex]\leq[/tex] -1.39) = 1 - P(Z < 1.39)

                                                            = 1 - 0.9177 = 0.0823

The above probability is calculated by looking at the value of x = 1.39 in the z table which has an area of 0.9177.                                        

Answer:

a) [tex]654.16-2.01\frac{165.4}{\sqrt{52}}=608.06[/tex]    

[tex]654.16+2.01\frac{165.4}{\sqrt{52}}=700.26[/tex]    

b) [tex]n=(\frac{1.960(175)}{25})^2 =188.23 \approx 189[/tex]

So the answer for this case would be n=189 rounded up to the nearest integer

Step-by-step explanation:

Part a

[tex]\bar X=654.16[/tex] represent the sample mean

[tex]\mu[/tex] population mean (variable of interest)

s=165.4 represent the sample standard deviation

n =52represent the sample size  

The confidence interval for the mean is given by the following formula:

[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]   (1)

The degrees of freedom aregiven by:

[tex]df=n-1=52-1=51[/tex]

Since the Confidence is 0.95 or 95%, the significance [tex]\alpha=0.05[/tex] and [tex]\alpha/2 =0.025[/tex], and the critical value would be [tex]t_{\alpha/2}=2.01[/tex]

Now we have everything in order to replace into formula (1):

[tex]654.16-2.01\frac{165.4}{\sqrt{52}}=608.06[/tex]    

[tex]654.16+2.01\frac{165.4}{\sqrt{52}}=700.26[/tex]    

Part b

The margin of error is given by this formula:

[tex] ME=z_{\alpha/2}\frac{s}{\sqrt{n}}[/tex]    (a)

And on this case we have that ME =25 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

[tex]n=(\frac{z_{\alpha/2} s}{ME})^2[/tex]   (b)

The critical value for this case wuld be [tex]z_{\alpha/2}=1.960[/tex], replacing into formula (b) we got:

[tex]n=(\frac{1.960(175)}{25})^2 =188.23 \approx 189[/tex]

So the answer for this case would be n=189 rounded up to the nearest integer

Answer:

Here you go!! :)

Step-by-step explanation:

Given that the sides of the quadrilateral are 3.3

The measure of one angle is 116°

We need to determine the value of x.

Value of x:

Since, the given quadrilateral is a rhombus because it has all four sides equal.

We know the property that the opposite sides of the rhombus are equal.

The measure of the opposite angle is 116°

x = measure of opposite angle

x = 116°

Then, the value of x is 116°

Therefore, the value of x is 116°

Answer:

In the diagram, the measurement of x is 87°

Step-by-step explanation:

In this diagram, this shape is a quadrilateral. This quadrilateral in this picture is known as rhombus. In a rhombus, the consecutive angles are supplementary meaning they have a sum of 180°. Consecutive means the angles are beside each other. So, we will subtract 93 from 180 to find the value of x.

180 - 93 = 87

The measurement of x is 87°

Answer:

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Step-by-step explanation:

The axis of symmetry is found by h = -b/2a  where ax^2 +bx +c

A. f(x) = x^2 + 4x + 3

  h = -4/2*1 = -2    x=-2

B. f(x) = x^2 - 4x - 5

h = - -4/2*1 = 4/2 =2  x=2  not -2

C. f(x) = x^2 + 6x + 2

h =  -6/2*1 = -3/2 =  x=-3/2  not -2

D. f(x) = -2x^2 - 8x + 1

h = - -8/2*-2 = 8/-4 =-2  x=-2  

E. f(x) = -2x^2 + 8x - 2

h = - 8/2*-2 = -8/-4 =2  x=2  not -2

Answer:

Hey there! The answer to this question is

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Answer:

I noticed a pattern:

3 * 2 + 6 = 12 and 2 * 2 + 5 = 9

This means that a*b = 2a + b.

━━━━━━━☆☆━━━━━━━

▹ Answer

2,013 cartons

▹ Step-by-Step Explanation

72,468 ÷ 36 = 2,013 cartons

Hope this helps!

CloutAnswers ❁

Brainliest is greatly appreciated!

━━━━━━━☆☆━━━━━━━

Answer:

72,468 eggs divided by 36 eggs per carton=2,013 cartons

Step-by-step explanation:

Answer:

y = (x + 3)^2 - 6.

Step-by-step explanation:

The vertex formula is Y = a(x - h)^2 + k.

To find the vertex formula, we need to find h and k, by finding the vertex of x^2 + 6x + 3.

h = -b/2a

a = 1, b = 6.

h = -6 / 2 * 1 = -6 / 2 = -3

k = (-3)^2 + 6(-3) + 3 = 9 - 18 + 3 = -9 + 3 = -6

So far, we have Y = a(x - (-3))^2 + -6, so y = a(x + 3)^2 - 6.

In this case, the coefficient of x^2 of the given formula is 1, which means that a will be 1.

The vertex form of x^2 + 6x + 3 is y = (x + 3)^2 - 6.

To check our work...

y = (x + 3)^2 - 6

= x^2 + 3x + 3x + 9 - 6

= x^2 + 6x + 3

Hope this helps!

Answer:

Quadrant II.

Step-by-step explanation:

Quadrant | has positive x and y coordinates.

Quadrant || has negative x and positive y coordinates.

Quadrant ||| has negative x and y coordinates.

Quadrant |V has positive x and negative y coordinates.

Since -3 is negative and 15 is positive, the answer is Quadrant II.

Answer:

x=98°

Step-by-step explanation:

The angles of a triangle must equal 180°.

To get the third angle (G) you must do: 180°-53°-45°

That will give you 82°

Anglr G and angle x create a straight line which is 180°.

so to get the answer you must do 180°-G=x

180°-82°=98°

Therefore x=98°

Answer:

873

Step-by-step explanation:

so the equation is: 5x+1

sum is:

[tex] \frac{first \: one \: + \: last \: one}{2} \times quantity \: of \: terms \\ [/tex]

we have 6( 5×1+1) to 91 (5×18+1)

so we have 18 terms

then:

[tex] \frac{91 + 6}{2} \times 18 = 873[/tex]

Answer:

11.5

Step-by-step explanation:

Put the numbers in order from smallest to largest

2,2,6,9,9,11,11,12,32,43,46,54,54,59

The median is the middle number

There are 14 numbers so the middle is between 7 and 8

2,2,6,9,9,11,11,    12,32,43,46,54,54,59

Take the average of the 7th and 8th numbers

(11+12)/2 = 11.5

The median is 11.5

Answer: 11.5

Step-by-step explanation:

The median is the middle number in a sorted list of numbers. So, to find the median, we need to place the numbers in value order and find the middle number.

Ordering the data from least to greatest, we get:

2   2   6   9   9   11   11   12   32   43   46   54   54   59    

As you can see, we do not have just one middle number but we have a pair of middle numbers, so the median is the average of these two numbers:

Median= 11+12/2=11.5

Answer:

1/8

Step-by-step explanation:

Total cards = 8

Card with 4 = 1

P(4) = 1/8

Answer:

[tex]\Large \boxed{\sf \ \ 28 \ \text{ and } \ 62 \ \ }[/tex]

Step-by-step explanation:

Hello, let's note a and b the two numbers.

We can write that

a = 6 + 2b

ab = 1736

So

[tex](6+2b)b=1736\\\\ \text{***Subtract 1736*** } <=> 2b^2+6b-1736=0\\\\ \text{***Divide by 2 } <=> b^2+3b-868=0 \\ \\ \text{***factorize*** } <=> b^2 +31b-28b-868=0 \\ \\ <=> b(b+31) -28(b+31)=0 \\ \\ <=> (b+31)(b-28) =0 \\ \\ <=> b = 28 \ \ or \ \ b = -31[/tex]

We are looking for positive numbers so the solution is b = 28

and then a = 6 +2*28 = 62

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

Answer:

Step-by-step explanation:

Can u help me

Answer:

cant see the picture

Step-by-step explanation:

Answer:

[tex]\boxed{\sf \ \ \ a=-2, \ b = 1 \ \ \ }[/tex]

Step-by-step explanation:

Hello,

saying that the function is continuous means that you cannot have a "jump" in the graph of the function

so we want

a*(-3)+b=7 and a*4+b=-7

it comes

   (1) -3a + b = 7

   (2) 4a + b = -7

(2)-(1) gives 4a + b + 3a - b =7a = -7-7 = -14

so a = -14/7 = -2

we replace in (1)

b = 7 + 3*(-2) = 7 - 6 = 1

hope this helps

Answer:

n = r - 2.5

Step-by-step explanation:

We have the following data:

7 4.5

8 5.5

10 7.5

12 9.5

Now, what we will do is what happens if we subtract each one:

7 - 4.5 = 2.5

8 - 5.5 = 2.5

10 - 7.5  = 2.5

12 - 9.5 = 2.5

The difference is always kept constant, therefore the equation would be:

n = r - 2.5

Answer: a) additive inverse (addition)

              b) multiplicative inverse (division)

Step-by-step explanation:

Step 2: 6 is being added to both sides

Step 4: (3/4) is being divided from both sides

It is difficult to know what options are provided in the drop-down menu without seeing them. If I was to complete a proof and justify each step, then the following justifications would be used:

Step 2: Addition Property of Equality

Step 4: Division Property of Equality

Answer:

  A.  (2, 4)

Step-by-step explanation:

The ordered pairs represent (x, y). Since you have y =2x, this is the same as ...

  (x, 2x)

That is, the second number in the pair needs to be twice the first number in the pair. Since you know your times tables, you know that this is not the case for (1, 0), (10, 5) or (4, 12). Those values of x would give (1, 2), (10, 20), (4, 8).

It is the case that you have (x, 2x) for (2, 4).

The point (2, 4) lies on the graph of y = 2x.

Assuming the coin is not weighted and is a fair and standard coin - the chance of flipping head is 1/2. You can either flip head or tails, there are no other possible outcomes.

Answer:

Step-by-step explanation:

[tex]x + 3 = 6[/tex]

Move constant to R.H.S and change its sign:

[tex]x = 6 - 3[/tex]

Calculate the difference

[tex]x = 3[/tex]

Hope this helps...

Good luck on your assignment..

Answer:

x  =  8   ( 20$ bills)

y  = 5    ( 10 $ bills)

z = 2     ( 5  $  bills)

Step-by-step explanation:

Let call x, y, and z the number of bill of 20, 10, and 5 $ respectively

then according to problem statement, we can write

20*x + 10*y + 5*z = 220         (1)

We also know the total number of bills (15), then

x + y + z = 15     (2)

And that quantity of 20 $ bill is equal to

x = 3 + y     (3)

Now we got a three equation system we have to solve for x, y, and z for which we can use any valid procedure.

As    x = 3 + y    by substitution in equation (2)   and (1)

( 3 + y ) + y + z  = 15       ⇒   3 + 2*y + z = 15  ⇒  2*y + z = 12

20* ( 3 + y ) + 10*y + 5*z  = 220  ⇒ 60 + 20*y + 10*y + 5*z = 220

30*y + 5*z  = 160      (a)

Now we have only 2 equations

2*y + z = 12   ⇒    z = 12 - 2*y

30*y + 5*z  = 160     30*y  + 5* ( 12 - 2*y) = 160

30*y  + 60 - 10*y = 160

20*y = 100

y = 100/20       y = 5      Then by substitution in (a)

30*y + 5*z = 160

30*5  + 5*z = 160

150 + 5*z  = 160    ⇒     5*z = 10     z = 10/5      z = 2

And x

x + y + z = 15

x + 5 + 2 = 15

x = 8

Answer:

x=8 y=5 x=2

Step-by-step explanation:

Complete Question

Which of the following statements are true?

I. The sampling distribution of [tex]\= x[/tex] has standard deviation [tex]\frac{\sigma}{\sqrt{n} }[/tex] even if the population is not normally distributed.

II. The sampling distribution of [tex]\= x[/tex]   is normal if the population has a normal distribution.

III. When  n is large, the sampling distribution of [tex]\= x[/tex]  is approximately normal even if the the population is not normally distributed.

A  I and II

B  I and III

C II and III

D I, II, and III

None of the above gives the complete set of true responses.

Answer:

The correct option is  D

Step-by-step explanation:

Generally the mathematically equation for evaluating the standard deviation of the mean([tex]\= x[/tex]) of samples is  [tex]\frac{\sigma}{\sqrt{n} }[/tex]  hence the the first statement is correct

   Generally the second statement is true, that is the sampling distribution of the mean ([tex]\= x[/tex]) is  normal given that the population distribution is  normal

 Now  according to central limiting theorem given that the sample size is  large the distribution of the mean ([tex]\= x[/tex]) is approximately  normal notwithstanding the distribution of the population

Answer:

25

Step-by-step explanation:

The method that should be used is substitution:

Do this by taking 3x+9y=21 and transforming it to be [tex]y=-\frac{1}{2} x+\frac{7}{3}[/tex]

Once you have this, substitute the value of y that we just found into 3x+9y=21 to find the value of x: [tex]3x+9(-\frac{1}{2} +\frac{7}{3} ) =21[/tex]

Solve for x. You should get 1.5

Once you have this, Plug in 1.5 for the value of x into the y= equation that we found in the beginning: [tex]y=-\frac{1}{2} (1.5)+\frac{7}{3}[/tex]

Solve for y. You should get 1.583 (19/12)

Plug in the values of x and y that we found into the last equation to find its value: 4(1.5+3(1.583))

Hey there! I'm happy to help!

We see that if the river isn't moving at all the boat can move at 18 mph (most likely because it has an engine propelling it.)

We want to set up a proportion where our 21 miles downstream time is equal to our 15 miles upstream time so we can find the speed. A proportion is basically showing that two ratios are equal. Since our downstream distance and upstream distance can be done in the same amount of time, we will write it as a proportion.

We want to find the speed of the river. We will use r to represent the speed of the river. When going downstream, the boat will go faster, so it will have a higher mph. So, our speed going down is 18+r. When you are going upstream, it's the opposite, so it will be 18-r.

[tex]\frac{distance}{speed} =\frac{21}{18+r} = \frac{15}{18-r}[/tex]

So, how do we figure out what r is now? Well, one nice thing to know about proportions is that the product of the items diagonal from each other equals the product of the other items. Basically, that means that 15(18+r) is equal to 21(18-r). This is a very nice trick to solve proportions quickly. We see that we have made an equation and now we can solve it!

15(18+r)=21(18-r)

We use the distributive property to undo the parentheses.

270+15r=378-21r

We subtract 270 from both sides.

15r=108-21

We add 21 to both sides.

36r=108

We divide both sides by 36.

r=3

Therefore, the speed of the river is 3 mph.

You also could have noticed that 18mph to 21 mph is +3, and 18mph to 15 mph -3 in -3 mph, so the speed of the river is 3 mph. That would have been a quicker way to solve it XD!

Have a wonderful day!

Answer:

[tex]t=\frac{50.857-51}{\frac{5.014}{\sqrt{7}}}=-0.075[/tex]    

The degrees of freedom are given by:

[tex]df=n-1=7-1=6[/tex]  

The p value for this case would be given:

[tex]p_v = 2*P(t_6 <-0.075)=0.943[/tex]

The p value for this case is lower than the significance level so then we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 51

Step-by-step explanation:

Info given

50, 53, 55, 43, 50, 47, 58.

We can calculate the sample mean and deviation with this formula:

[tex]\bar X=\frac{\sum_{i=1}^n X_i}{n}[/tex]

[tex]s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2)}{n-1}}[/tex]

represent the mean height for the sample  

[tex]s=5.014[/tex] represent the sample standard deviation for the sample  

[tex]n=7[/tex] sample size  

represent the value that we want to test

[tex]\alpha=0.05[/tex] represent the significance level for the hypothesis test.  

t would represent the statistic (variable of interest)  

[tex]p_v[/tex] represent the p value

Hypothesis to test

We want to test if the true mean is equal to 51, the system of hypothesis would be:  

Null hypothesis:[tex]\mu = 51[/tex]  

Alternative hypothesis:[tex]\mu \neq 51[/tex]  

The statistic is given by:

[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex]  (1)  

Replacing we got:

[tex]t=\frac{50.857-51}{\frac{5.014}{\sqrt{7}}}=-0.075[/tex]    

The degrees of freedom are given by:

[tex]df=n-1=7-1=6[/tex]  

The p value for this case would be given:

[tex]p_v = 2*P(t_6 <-0.075)=0.943[/tex]

The p value for this case is lower than the significance level so then we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 51

Answer:

(a) -3125, 15625

(b)

[tex]a_n=-5a_{n-1}, \\n\geq 2 \\a_1=1[/tex]

(c)[tex]a_n=(-5)^{n-1}[/tex]

Step-by-step explanation:

The sequence [tex]a_n$ _{n=1}^\infty[/tex] is given as:

[tex]\{1,-5,25,-125,625,\cdots\}[/tex]

(a)The next two terms of the sequence are:

625 X -5 = - 3125

-3125 X -5 =15625

(b)Recurrence Relation

The recurrence relation that generates the sequence is:

[tex]a_n=-5a_{n-1}, \\n\geq 2 \\a_1=1[/tex]

(c)Explicit Formula

The sequence is an alternating geometric sequence where:

Therefore, an explicit formula for the sequence is:

[tex]a_n=1\times (-5)^{n-1}\\a_n=(-5)^{n-1}[/tex]