A normal distribution has a mean of 30 and a variance of 5.Find N such that the probability that the mean of N observations exceeds 30.5 is 1%.​

Answer:

The  probability is  [tex]P(X \le 0.305 ) = 0.01795[/tex]

Step-by-step explanation:

From the question we are told that

      The population mean is  [tex]\mu = 0.966 \ grams[/tex]

       The standard deviation is  [tex]\sigma = 0.315 \ grams[/tex]

Given that the amounts of nicotine in a certain brand of cigarette are normally distributed

    Then the probability of randomly selecting a cigarette with 0.305 grams of nicotine or less is mathematically represented as

        [tex]P(X \le 0.305 ) = 1 - P(X > 0.305) = 1 - P(\frac{X - \mu }{\sigma } > \frac{0.305 - \mu }{\sigma } )[/tex]

Generally

              [tex]\frac{X - \mu }{\sigma } = Z (The \ standardized \ value \ of X )[/tex]

So  

      [tex]P(X \le 0.305 ) = 1 - P(X > 0.305) = 1 - P(Z > \frac{0.305 - 0.966 }{0.315} )[/tex]

      [tex]P(X \le 0.305 ) = 1 - P(X > 0.305) = 1 - P(Z >-2.0984 )[/tex]

From the z-table(reference calculator dot  net  ) value of   [tex]P(Z >-2.0984 ) =0.98205[/tex]

So  

     [tex]P(X \le 0.305 ) = 1 - P(X > 0.305) = 1 - 0.98205[/tex]

=>  [tex]P(X \le 0.305 ) = 1 - P(X > 0.305) = 0.01795[/tex]

=> [tex]P(X \le 0.305 ) = 0.01795[/tex]

Answer:

C(4,6)

Step-by-step explanation:

the x turns into its opposite when reflected across y same thing for y when reflected across x

Answer:

c. (4, 6)

Step-by-step explanation:

The rule of an reflection about the y-axis is: [tex]A(x,y)\rightarrow A'(-x,y)[/tex]

Apply the rule to  point (-4, 6):

[tex]\frac{(-4,6)\rightarrow\boxed{(4,6)}}{(x,y)\rightarrow(-x,y)}[/tex]

Option C should be the correct answer.

Answer:

Z= 0.253

Z∝/2 = ± 1.96

Step-by-step explanation:

Formulate the null and alternative hypotheses as

H0 : u1= u2 against Ha : u1≠ u2 This is a two sided test

Here ∝= 0.005

For alpha by 2 for a two tailed test Z∝/2 = ± 1.96

Standard deviation = s= 15

n= 10

The test statistic used here is

Z = x- x`/ s/√n

Z= 2058- 2046 / 15 / √10

Z= 0.253

Since the calculated value of Z= 0.253 falls in the critical region we reject the null hypothesis.

There is  evidence at the 0.05 level that the doors are too short and unusable.

Answer:  4  inches

Step-by-step explanation:

1. We gonna find the the length of the right triangle legs using Phitagor theorem.

c²=a²+b²  (1)   , where c is triangle's  hypotenuse

a and b are the triangle's  legs.

Let the leg a =x,    so leg b=x+1 inches

Now we can write the equation using (1)

25=x²+(x+1)²

25=x²+x²+2*x+1

2*x²+2*x-24=0     ( divide by 2 both sides of the equation)

x²+x-12=0

Find the discriminant D=1+12*4=49

√D=7

x1= (-1+7)/2=3     x2=(-1-7)/2=-4 - x2=-4 not possible so length of the leg can not be negative.

So the shorter leg a=x= 3 inches

The longer leg b=x+1=4 inches

Step-by-step explanation:

For a left-hand limit, we start at the left side and move right, and see where the function goes as we get close to the x value.

For a right-hand limit, we start at the right side and move left, and see where the function goes as we get close to the x value.

If the two limits are equal, then the limit exists.  Otherwise, it doesn't.

1.  As we approach x = 2 from the left, f(x) approaches -2.

lim(x→2⁻) f(x) = -2

As we approach x = 2 from the right, f(x) approaches 1.

lim(x→2⁺) f(x) = 1

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

2. As we approach x = 2 from the left, f(x) approaches 4.

lim(x→2⁻) f(x) = 4

As we approach x = 2 from the right, f(x) approaches 2.

lim(x→2⁺) f(x) = 2

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

3. As we approach x = 2 from the left, f(x) approaches 2.

lim(x→2⁻) f(x) = 2

As we approach x = 2 from the right, f(x) approaches 2.

lim(x→2⁺) f(x) = 2

The limits are equal, so the limit exists.

lim(x→2) f(x) = 2

4. As we approach x = 2 from the left, f(x) approaches 2.

lim(x→2⁻) f(x) = 2

As we approach x = 2 from the right, f(x) approaches infinity.

lim(x→2⁺) f(x) = ∞

The limits are not the same, so the limit does not exist.

lim(x→2) f(x) = DNE

Answer:

[tex]D = 42.5\ inch[/tex]

Step-by-step explanation:

Given

[tex]L = Length[/tex] and [tex]W = Width[/tex]

[tex]L:W = 8: 5[/tex]

[tex]Perimeter = 117[/tex]

Required

Determine the Diagonal

First, the dimension of the screen has to be calculated;

Recall that; [tex]L:W = 8: 5[/tex]

Convert to division

[tex]\frac{L}{W} = \frac{8}{5}[/tex]

Multiply both sides by W

[tex]W * \frac{L}{W} = \frac{8}{5} * W[/tex]

[tex]L = \frac{8W}{5}[/tex]

The perimeter of a rectangle:

[tex]Perimeter = 2(L+W)[/tex]

Substitute [tex]L = \frac{8W}{5}[/tex]

[tex]Perimeter = 2(\frac{8W}{5}+W)[/tex]

Take LCM

[tex]Perimeter = 2(\frac{8W + 5W}{5})[/tex]

[tex]Perimeter = 2(\frac{13W}{5})[/tex]

Substitute 117 for Perimeter

[tex]117 = 2(\frac{13W}{5})[/tex]

[tex]117 = \frac{26W}{5}[/tex]

Multiply both sides by [tex]\frac{5}{26}[/tex]

[tex]\frac{5}{26} * 117 = \frac{26W}{5} * \frac{5}{26}[/tex]

[tex]\frac{5 * 117}{26} = W[/tex]

[tex]\frac{585}{26} = W[/tex]

[tex]22.5 = W[/tex]

[tex]W = 22.5[/tex]

Recall that

[tex]L = \frac{8W}{5}[/tex]

[tex]L = \frac{8 * 22.5}{5}[/tex]

[tex]L = \frac{180}{5}[/tex]

[tex]L = 36[/tex]

The diagonal of a rectangle is calculated using Pythagoras theorem as thus;

[tex]D = \sqrt{L^2 + W^2}[/tex]

Substitute values for L and W

[tex]D = \sqrt{36^2 + 22.5^2}[/tex]

[tex]D = \sqrt{1296 + 506.25}[/tex]

[tex]D = \sqrt{1802.25}[/tex]

[tex]D = \sqrt{1802.25}[/tex]

[tex]D = 42.4529150943[/tex]

[tex]D = 42.5\ inch[/tex] (Approximated)

Answer:

I have not answer

plz follow me....

Answer:

Step-by-step explanation:

Let the number to be found be x

The product of a number and 3 is written as

15 minus twice the number is written as

Now equate the two statements

That's

3x = 15 - 2x

Group like terms

3x + 2x = 15

5x = 15

Divide both sides by 5

the final answer is

Hope this helps you

Answer:

hi

Step-by-step explanation:

Answer:

6

Step-by-step explanation:

3/4=6/8

6/8-1/8=5/8

So 5/8 of the tank is 15 gallons.  This means each 1/8 of a tank is 3 gallons.

The van is currently 6/8 full. We need to add another 2/8 to completely fill the tank.  

2x3=6

You’ll need 6 more gallons to fill the tank.

Answer:

Mean= $21.5067

Median = $15.8

Standard deviation= $19.02

Coefficient of skewness= $0.8991

Step-by-step explanation:

Mean =( $4.0 +$6.0 +$7.4+ $10.6 +$12.5+ $13.6+ $15.4+ $15.8 +$16.8

+$17.4+ $19.1 +$22.3+ $37.1 +$43.2 +$81.4)/15

Mean =$ 322.6/15

Mean= $21.5067

Median= middle number

Median = $15.8

Variance=( ($4.0-.$21.5)²+( $6.0. -.$21.5)²+( $7.4 -.$21.5)²+( $10.6 -.$21.5)²+( $12.5 -.$21.5)²+( $13.6. -.$21.5)²+ ($15.4 -.$21.5)²+( $15.8 -.$21.5)²+ ( $16.8 -.$21.5)²+ ($17.4-.$21.5)² +($19.1 -.$21.5)²+ ($22.3 -.$21.5)²+ ($37.1 -.$21.5)²+ ($43.2-.$21.5)²+( $81.4-.$21.5)²)/15

Variance=$ 5424.79/15

Variance=$ 361.65

Standard deviation= √ variance

Standard deviation= √361.65

Standard deviation= $19.02

Coefficient of skewness

=3( mean-median)/standard deviation

= 3(21.5-15.8)/19.02

= 3(5.7)/19.02

= 17.1/19.02

Coefficient of skewness= 0.8991

Answer: -3

Step-by-step explanation: 2x = -2 then you subtract 1 from that which is the same as adding negative one so -2 - 1 or -2 + -1 = -3

Answer:

No, F* < Fc

Step-by-step explanation:

Significance level or alpha level is the probability of rejecting the null hypothesis when null hypothesis is true. It is considered as a probability of making a wrong decision. It is a statistical test which determines probability of type I  error. If the obtained probability is equal of less than critical probability value then reject the null hypothesis .

Answer:

The probability that the sample mean is more than 110 is 0.0384.

Step-by-step explanation:

According to the Central Limit Theorem if we have an unknown population with mean μ and standard deviation σ and appropriately huge random samples (n > 30) are selected from the population with replacement, then the sampling distribution of the sample mean will be approximately normally distributed.  

Then, the mean of the sampling distribution of sample mean is given by:

[tex]\mu_{\bar x}=\mu[/tex]

And the variance of the sampling distribution of sample mean is given by:

[tex]\sigma^{2}_{\bar x}=\frac{\sigma^{2}}{n}[/tex]

The information provided is:

[tex]n=50\\\\\mu=100\\\\\sigma^{2}=1600[/tex]

Since n = 50 > 30, the central limit theorem can be applied to approximate the sampling distribution of sample mean by the normal distribution.

The mean variance of the sampling distribution for the sample mean are:

[tex]\mu_{\bar x}=\mu=100\\\\\sigma^{2}_{\bar x}=\frac{\sigma^{2}}{n}=\frac{1600}{50}=32[/tex]

That is, [tex]\bar X\sim N(100, 32)[/tex].

Compute the probability that the sample mean is more than 110 as follows:

[tex]P(\bar X>110)=P(\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}>\frac{110-100}{\sqrt{32}})[/tex]

                   [tex]=P(Z>1.77)\\=1-P(Z<1.77)\\=1-0.96164\\=0.03836\\\approx 0.0384[/tex]

*Use a z-table.

Thus, the probability that the sample mean is more than 110 is 0.0384.

Answer:

Step-by-step explanation:

The graph tells you the zeros of the function are x=-3/4 and x=4.

The y-intercept is the constant in the function: 12.

The maximum is 22.5625 at x = 1.625.

Answer: 0.20

Step-by-step explanation:

The given probability distribution of number of televisions per household in a small town:

x          0       1     2      3

​P(x) ​ 0.05 0.15 0.25 0.55

To find : The probability of randomly selecting a household that has one or two televisions ( in both parts a. and b.).

The computations for this would be :

P( 1 or 2) = P(1)+P(2)

= 0.05+0.15

= 0.20

Hence, the required probability= 0.20

Answer:

Step-by-step explanation:

Answer:

x = 20°

Step-by-step explanation:

So when I learned it we called it the exterior angle theorem not the angle sum theorem but here goes.

Since exterior angle = 110 Degrees,

--> The Inner 2 angles's sum = 110 Degrees

so, 70 + 2x = 110

=> 2x = 40

x = 20

x = 20°

Hope this helps!

Answer:

6 years

Step-by-step explanation:

A parent increases a child’s monthly allowance by 20% each year. If the allowance is $8 per month now. This is an exponential function, An exponential function is given by:

[tex]y=ab^x[/tex]

Let x be the number of years and y be the allowance. The initial allowance is $8, this means at x = 0, y = 8

[tex]y=ab^x\\8=ab^0\\a=8[/tex]

Since it increases by 20% each year, i.e 100% + 20% = 1 + 0.2 = 1.2. This means that b = 1.2

Therefore:

[tex]y=ab^x\\y=8(1.2^x) \\[/tex]

To find the number of years will it take to reach $20 per month, we substitute y = 20 and find x

[tex]20=8(1.2)^x\\20/8=1.2^x\\1.2^x=2.5\\Taking \ natural\ log\ of \ both\ sides:\\ln(1.2^x)=ln2.5\\xln(1.2)=0.9163\\x=0.9163/ln(1.2)\\x=5.026[/tex]

x = 6 years to the nearest year

Answer:

5 years

Step-by-step explanation:444

Answer:

2y= 6-3x when x=0

2y= 6-3(0)

2y= 6-0

2y= 6

y= 6/2

y= 3

#i'm indonesian

#hope it helps.

Answer:

[tex] \boxed{y = 3}[/tex]

Step-by-step explanation:

Given, x = 0

[tex] \mathsf{2y = 6 - 3x}[/tex]

plug the value of x

⇒[tex] \mathsf{2y = 6 - 3 \times 0}[/tex]

Multiply the numbers

⇒[tex] \mathsf{2y = 6 - 0}[/tex]

Calculate the difference

⇒[tex] \mathsf{2y = 6}[/tex]

Divide both sides of the equation by 2

⇒[tex] \mathsf{ \frac{2y}{2} = \frac{6}{2} }[/tex]

Calculate

⇒[tex] \mathsf{y = 3}[/tex]

Hope I helped!

Best regards!

Answer:

18 minutes

Step-by-step explanation:

A = A₀ (½)^(t / T)

where A is the final amount,

A₀ is the initial amount,

t is the time,

and T is the half life.

A = 140 when t = 10.  Solve for the half life:

140 = 700 (½)^(10 / T)

0.2 = ½^(10 / T)

log 0.2 = (10 / T) log 0.5

10 / T = 2.32

T = 4.31

When A = 40, t is:

40 = 700 (½)^(t / 4.31)

0.057 = ½^(t / 4.31)

log 0.057 = (t / 4.31) log 0.5

t / 4.31 = 4.13

t = 17.8

Rounded to the nearest whole number, it takes 18 minutes.

The time taken for bacteria to reach 40 according to the exponential half-life decay formula is 18 minutes.

In mathematics, an exponential function is a relationship of the type y = ax, where x is an independent variable that spans the entire real number line and is expressed as the exponent of a positive number.

The half-life decay formula is given as,

N(t) = N₀ [tex](1/2)^{(t / T)}[/tex]

Where T is half-life while t is the time taken.

N₀ is the initial amount,

As per the given,

N(t) = 140 when t = 10.

140 = 700 [tex](1/2)^{(t / T)}[/tex]

Take log both sides,

log 0.2 = (10 / T) log 0.5

10 / T = 2.32

T = 4.31 minutes

Put N(t) = 40

40 = 700[tex](1/2)^{(t / 4.31)}[/tex]

Take log both sides,

log 0.057 = (t / 4.31) log 0.5

t / 4.31 = 4.13

t = 17.8 ≈ 18 minutes

Hence "The time taken for bacteria to reach 40 according to the exponential half-life decay formula is 18 minutes".

For more about exponential function,

https://brainly.com/question/15352175

#SPJ2

Hey there! I'm happy to help!

To find the volume of a cube, you simply take whatever the side length is and multiply it by itself 3 times, which is also known as cubing the number!

16×16×16=4096

You can also write it as 16³=4096

This is because the length is 16, the width is 16, and the height is 16, so you multiply them all together!

I hope that this helps! Have a wonderful day!

Answer:

[tex]a \leqslant 10[/tex]

Step-by-step explanation:

a is less than or equal to 10

less than: <

equal: =

less than or equal to: ≤

Hope this helps ;) ❤❤❤

hope it helps you

imp=draw dark shaded point in thqt line and point towards left

Answer:

x=1

Step-by-step explanation:

3(x + 1)= -2(x - 1) + 6.

Distribute

3x+3 = -2x+2+6

Combine like terms

3x+3 = -2x+8

Add 2x to each side

3x+3+2x = 8

5x+3 = 8

Subtract 3 from each side

5x =5

Divide by 5

x =1

Answer:

36.9°

Step-by-step explanation:

Sin x = 9/15 = 3/5

x = sin^-1 3/5

x= 36.87

x= 36.9° to nearest tenth

Answer:

The system of equations you want to be solved is not given. I would however give an example with which the method of elimination will be shown, and can be used in solving problems of the nature.

Step-by-step explanation:

Consider the system of equations:

x + y = 7 ................................(1)

2x - y = 8 ..............................(2)

To eliminate x:

First multiply (1) by 2 to have

2x + 2y = 14 ...........................(3)

Next, subtract (2) from (3) to have

3y = 6

y = 6/3 = 2

To eliminate y:

Add (1) and (2) to have

3x = 15

x = 15/3 = 5

Therefore, (x, y) = (5, 2).

Aqui temos a seguinte divisao de terreno:

creche + banheiros + academia = 45% + 3% + 12% = 60%

O que sobra: Fazendo a conta, 100 - 60 = 40, restará 40%

No enunciado informa que sobraram 960m².

Logo concluimos que 40% = 960m²

Sendo assim, regra de 3:

   m²                %

  960   --------   40

    X     --------   60

40X = 960 . 60

X = 57600/40

X = 1440

Logo 1440m² é destinado para: creche, banheiros públicos e academia

de ginástica comunitária.

O terreno tem um total de 1440 + 960 = 2400m²

para cada espaço - novamente diversas regra de 3:

→ creche = 45%

    m²                  %

  2400   --------   100

    X        --------    45

X = 108000/100 = 1080

→ banheiros públicos  = 3%

    m²                  %

  2400   --------   100

    X        --------    3

X = 7200/100 = 72

→ academia de ginástica comunitária = 12%

    m²                  %

  2400   --------   100

    X        --------    12

X = 28800/100 = 288

provando:

60% = 1440m²  (visto acima)

creche - 1080

banheiros - 72

academia - 288

1080 + 72 + 288 = 1440 (60%)

Answer:

2.7 in²

Step-by-step explanation:

Area of ∆BAC : ∆Area of EDF = BC² : EF² (based on the area of similar triangles theorem)

Thus:

[tex] 6 in^2 : x in^2 = (3 in)^2 : (2 in)^2 [/tex]

[tex]\frac{6}{x} = \frac{3^2}{2^2}[/tex]

[tex]\frac{6}{x} = 2.25[/tex]

[tex]\frac{6}{x}*x = 2.25*x[/tex]

[tex]6 = 2.25x[/tex]

[tex]\frac{6}{2.25} = \frac{2.25x}{2.25}[/tex]

[tex]2.67 = x[/tex]

Area of ∆EDF = 2.7 in²

Answer:

1) the domain is all real numbers

2) the range is

[tex]y \geqslant 3[/tex]

Answer:

The answer is below

Step-by-step explanation:

The box contains 5 red and 4 white balls.

A) The probability that at least 1 ball was​ red = P(both are red) + P(first is red and second is white) + P(first is white second is red)

Given that the first ball was (Upper A )Replaced before the second draw:

P(both are red) = P(red) × P(red) = 5/9 × 5/9 = 25/81

P(first is red and second is white) = P(red) × P(white) = 5/9 × 4/9 = 20/81

P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/9 = 20/81

The probability that at least 1 ball was​ red = 25/81 + 20/81 + 20/81 = 65/81

B) The probability that at least 1 ball was​ red = P(both are red) + P(first is red and second is white) + P(first is white second is red)

Given that the first ball was not Replaced before the second draw:

P(both are red) = P(red) × P(red) = 5/9 × 4/8 = 20/72 (since it was not replaced after the first draw the number of red ball remaining would be 4 and the total ball remaining would be 8)

P(first is red second is white) = P(red) × P(white) = 5/9 × 4/8 = 20/72

P(first is white and second is red) = P(white) × P(red) = 4/9 × 5/8 = 20/72

The probability that at least 1 ball was​ red = 20/72 + 20/72 + 20/72 = 60/72