Michelle is 7 years older than her sister Joan, and Joan is 3 years younger than their brother Ryan. If the sum of their ages is 64, how old is Joan?

16
22
18
19

Answer:

9-x^2

Step-by-step explanation:

The difference of means subtracting. the first number is 9 and the second is x^2, so you get 9-x^2

Answer:

Simplify:

[tex]-4^2-5(1^3)[/tex]

So you get:

[tex]-21\\[/tex]

Answer:

[tex]\huge\boxed{-21}[/tex]

Step-by-step explanation:

-x²-5y³

Given that x = 4, y = 1

[tex]-(4)^2-5(1)^3[/tex]

[tex]-16-5(1)\\-16-5\\-21[/tex]

Answer:

109

Step-by-step explanation:

Use a chart or calculator to find the z-score corresponding to a probability of 1%.

P(Z > z) = 0.01

P(Z < z) = 0.99

z = 2.33

Now find the sample standard deviation.

z = (x − μ) / s

2.33 = (30.5 − 30) / s

s = 0.215

Now find the sample size.

s = σ / √n

s² = σ² / n

0.215² = 5 / n

n = 109

Complete question is;

A manufacturer claims that the calling range (in feet) of its 900-MHz cordless telephone is greater than that of its leading competitor. A sample of 19 phones from the manufacturer had a mean range of 1160 feet with a standard deviation of 32 feet. A sample of 11 similar phones from its competitor had a mean range of 1130 feet with a standard deviation of 30 feet. Required:

Do the results support the manufacturer's claim?

Let μ1 be the true mean range of the manufacturer's cordless telephone and μ2 be the true mean range of the competitor's cordless telephone. Use a significance level of α = 0.01 for the test. Assume that the population variances are equal and that the two populations are normally distributed

Answer:

We will fail to reject the null hypothesis as there is no sufficient evidence to support the manufacturers claim.

Step-by-step explanation:

For the first sample, we have;

Mean; x'1 = 1160 ft

standard deviation; σ1 = 32 feet

Sample size; n1 = 19

For the second sample, we have;

Mean; x'2 = 1130 ft

Standard deviation; σ2 = 30 ft

Sample size; n2 = 11

The hypotheses are;

Null Hypothesis; H0; μ1 = μ2

Alternative hypothesis; Ha; μ1 > μ2

The test statistic formula for this is;

z = (x'1 - x'2)/√[(σ1)²/n1) + (σ2)²/n2)]

Plugging in the relevant values, we have;

z = (1160 - 1130)/√[(32)²/19) + (30)²/11)]

z = 2.58

From the z-table attached, we have a p-value = 0.99506

This p-value is more than the significance value of 0.01,thus,we will fail to reject the null hypothesis as there is no sufficient evidence to support the manufacturers claim.

Answer:

3/4 is the slope

Step-by-step explanation:

We want to put this in slope intercept form

y = mx+b  where m is the slope and b is the y intercept

0 = -12 + 4y - 3x

Subtract 4y from each side

-4y = -3x-12

Divide each side by -4

-4y/-4 = -3x/-4 -12/-4

y = 3/4 x +3

Answer:

Slope=3/4

Step-by-step explanation:

0=-12+4y-3x (Add 12 on the other side)

12=4y-3x (Add 3x on the other side)

3x+12=4y (Divide by 4)

y=3/4+3

Answer:

Step-by-step explanation:

Initial population in 2018 = 25,000

Annual growth rate (in %) = 4%

Yearly Increment in population = 4% of 25000

= 4/100 * 25000

= 250*4

= 1000

This means that the population increases by 1000 on yearly basis.

To determine what the  population will be in 2033, we need to first know the amount of years we have between 2018 and 2033.

Amount of years we have between 2018 and 2033 = 2033-2018

= 15 years

After 15 years, the population will have increased by 15*1000 i.e 15,000 more than the initial population.

Hence the population in 2033 will be Initial population + Increment after 15years = 25,000+15000 = 40,000 population.

Answer:

a

   [tex]P(X < 2500) = 0.02668[/tex]

b

   [tex]P(X < 1500) = 0.00001[/tex]

Step-by-step explanation:

From the question we are told that

     The  population mean  is  [tex]\mu = 3350[/tex]

      The standard deviation is  [tex]\sigma = 440[/tex]

We also told in the question that the birth weight is  approximately Normally distributed

    i.e      [tex]X \ \~ \ N(\mu , \sigma )[/tex]

Given that Low-birth-weight babies weighing less than 2500 grams,then the proportion of babies born full term are low-birth-weight babies is mathematically represented as

       [tex]P(X < 2500) = P(\frac{ X - \mu }{\sigma } < \frac{2500 - \mu}{\sigma } )[/tex]

Generally  

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

So

      [tex]P(X < 2500) = P(Z < \frac{2500 - \mu}{\sigma } )[/tex]

substituting values

      [tex]P(X < 2500) = P(Z < \frac{2500 - 3350}{440 } )[/tex]

       [tex]P(X < 2500) = P(Z <-1.932 )[/tex]

Now from the standardized normal distribution table(These value can also be obtained from Calculator dot com) the value of

     [tex]P(Z <-1.932 ) = 0.02668[/tex]

=>    [tex]P(X < 2500) = 0.02668[/tex]

Given that  very-low-birth-weight babies (weighing less than 1500 grams,then the  proportion of babies born full term are very-low-birth-weight babies is mathematically represented as

    [tex]P(X < 1500) = P(\frac{ X - \mu }{\sigma } < \frac{1500 - \mu}{\sigma } )[/tex]

    [tex]P(X < 1500) = P(Z < \frac{1500 - \mu}{\sigma } )[/tex]

substituting values

           [tex]P(X < 1500) = P(Z < \frac{1500 - 3350}{440 } )[/tex]

       [tex]P(X < 1500) = P(Z <-4.205 )[/tex]

Now from the standardized normal distribution table(These value can also be obtained from calculator dot com) the value of

     [tex]P(Z <-1.932 ) = 0.00001[/tex]

    [tex]P(X < 1500) = 0.00001[/tex]

Answer:

(0.102, -0.062)

Step-by-step explanation:

sample size in 2018 = n1 = 216

sample size in 2017 = n2 = 200

number of people who went for another degree in 2018 = x1 = 54

number of people who went for another degree in 2017 = x2 = 46

p1 = x1/n1 = 0.25

p2 = x2/n2 = 0.23

At 95% confidence level, z critical = 1.96

now we have to solve for the confidence interval =

[tex]0.25 -0.23 ± 1.96*\sqrt{((1 - 0.25) * 0.25)/216 + ((1 - 0.23) *0.23/200}[/tex]

= 0.02 ± 1.96 * 0.042

= 0.02 + 0.082 = 0.102

= 0.02 - 0.082 = -0.062

There is 95% confidence that there is a difference that lies between  - 0.062 and 0.102 on the proportion of students who continued their education in the years, 2017 and 2018.

There is no significant difference between the two.

Answer:

  b.  $11,820

Step-by-step explanation:

The 'rule of 72' tells you the doubling time of this account is about ...

  (72 years)/(4.25) = 16.9 years

So, in 18 years, the amount will be slightly more than double the present value. That is, the present value is slightly less than half the future amount.

  $25,000/2 = $12,500

The closest answer choice is ...

  $11,820

__

The present value of that future amount is ...

  PV = FV×(1 +r)^-t = $25,000×1.0425^-18 ≈ $11,818.73

The present value is about $11,820.

Answer:

B

Step-by-step explanation:

a. y = 2.5x + 2000

b. The variable x represents the domain because the domain is the range of the possible x values.

c. x ≥ 0

d. The variable y represents the range because the range is the range of the possible y values.

e. y ≥ 2000

f. y = 2.5(25) + 2000

  y = 62.5 + 2000

  y = $2062.50

g. 2500 = 2.5x + 2000

   2.5x = 500

   x = 200

h. I am sorry I cannot make the graph but hopefully you can figure out how to make it using the info I have given in the above parts of the problem :)

Answer:

3x - 4

Step-by-step explanation:

As Tina's age is 3 into x ( 3 x x= 3x)but 4years less (-4)

Therefore Tina's age is 3x - 4

Answer:

3x - 4

Step-by-step explanation:

Use these representations:  niece's age: x

We triple x and then subract 4 years from the result, obtaining:

Tina's age:  3x - 4

Answer:

The unknown integer that solves the equation is 6.

Step-by-step explanation:

In order to find the missing number, we can set up an equation as if we are solving for x.

x + (-8) = -2

Add 8 on both sides of the equation.

x = 6

So, the unknown integer is 6.

Answer:

6

Step-by-step explanation:

6 plus -8 is -2

Hey There!!

The answer to this is: A quadrilateral has vertices A(3, 5), B(2, 0), C(7, 0), and D(8, 5). Which statement about the quadrilateral is true?" Line BC is parallel to line AD because their slopes is equal i.e. (0 - 0) / (7 - 2) = (5 - 5) / (8 - 3) which gives 0 / 5 = 0 / 5 giving that 0 = 0. We check whether line AB is parallel to line CD. Slope of line AB is given by (0 - 5) / (2 - 3) = -5 / -1 = 5. Slope of line CD is given by (5 - 0) / (8 - 7) = 5 / 1 = 5 We have been able to prove that the opposite sides of the quadrilateral are parallel which means that the quadrilateral is not a trapezoid. Next we check whether the length of the sides are equal. Length of line AB is given by sqrt[(0 - 5)^2 + (2 - 3)^2] = sqrt[(-5)^2 + (-1)^2] = sqrt(25 + 1) = sqrt(26) Length of line BC is given by sqrt[(0 - 0)^2 + (7 - 2)^2] = sqrt[0^2 + 5^2] = sqrt(25) = 5 Length of line CD is given by sqrt[(5 - 0)^2 + (8 - 7)^2] = sqrt[5^2 + 1^2] = sqrt(25 + 1) = sqrt(26) Length of line DA is given by sqrt[(5 - 5)^2 + (8 - 3)^2] = sqrt[0^2 + 5^2] = sqrt(25) = 5 Thus, the length of the sides of the quadrilateral are not equal but opposite sides are equal which means that the quadrilateral is not a rhombus. Finally, we check whether adjacent lines are perpendicular. Recall the for perpendicular lines, the product of their slopes is equal to -1. Slope of line AB = 5 while slope of line BC = 0. The product of their slopes = 5 x 0 = 0 which is not -1, thus the adjacent sides of the quadrilateral are not perpendicular which means that the quadrilateral is not a rectangle. Therefore, ABCD is a parallelogram with non-perpendicular adjacent sides. Thus, For (option A).

Hope It Helped!~ ♡

ItsNobody~ ☆

Answer:

A. ABCD is a parallelogram with non-perpendicular adjacent sides.

Hope this helps!

Step-by-step explanation:

Answer:

[tex]\approx \bold{6544\ in^3/sec}[/tex]

Step-by-step explanation:

Given:

Rate of change of radius of cylinder:

[tex]\dfrac{dr}{dt} = +7\ in/sec[/tex]

(This is increasing rate so positive)

Rate of change of height of cylinder:

[tex]\dfrac{dh}{dt} = -6\ in/sec[/tex]

(This is decreasing rate so negative)

To find:

Rate of change of volume when r = 20 inches and h = 16 inches.

Solution:

First of all, let us have a look at the formula for Volume:

[tex]V = \pi r^2h[/tex]

Differentiating it w.r.to 't':

[tex]\dfrac{dV}{dt} = \dfrac{d}{dt}(\pi r^2h)[/tex]

Let us have a look at the formula:

[tex]1.\ \dfrac{d}{dx} (C.f(x)) = C\dfrac{d(f(x))}{dx} \ \ \ (\text{C is a constant})\\2.\ \dfrac{d}{dx} (f(x).g(x)) = f(x)\dfrac{d}{dx} (g(x))+g(x)\dfrac{d}{dx} (f(x))[/tex]

[tex]3.\ \dfrac{dx^n}{dx} = nx^{n-1}[/tex]

Applying the two formula for the above differentiation:

[tex]\Rightarrow \dfrac{dV}{dt} = \pi\dfrac{d}{dt}( r^2h)\\\Rightarrow \dfrac{dV}{dt} = \pi h\dfrac{d }{dt}( r^2)+\pi r^2\dfrac{dh }{dt}\\\Rightarrow \dfrac{dV}{dt} = \pi h\times 2r \dfrac{dr }{dt}+\pi r^2\dfrac{dh }{dt}[/tex]

Now, putting the values:

[tex]\Rightarrow \dfrac{dV}{dt} = \pi \times 16\times 2\times 20 \times 7+\pi\times 20^2\times (-6)\\\Rightarrow \dfrac{dV}{dt} = 22 \times 16\times 2\times 20 +3.14\times 400\times (-6)\\\Rightarrow \dfrac{dV}{dt} = 14080 -7536\\\Rightarrow \dfrac{dV}{dt} \approx \bold{6544\ in^3/sec}[/tex]

So, the answer is: [tex]\approx \bold{6544\ in^3/sec}[/tex]

Answer:

x=9.6

Step-by-step explanation:

The dot in the middle represents the center of the circle, so therefore, the line that is represented by 16 is the radius. Since that is the radius, the side that is the hypotenuse of the small triangle is also 16, since they have the same distance.

The line represented by 25.6 with x as its bisector shows that when we divide it by 2, the other side of the triangle besides the hypotenuse is 12.8.

Now that we have the two sides of the triangle, we can find the last side (represented by x). Use pythagorean theorem:

[tex]a^2 +b^2=c^2\\x^2+(12.8)^2=16^2\\x^2+163.84=256\\x^2=92.16\\x=9.6[/tex]

Answer:

1)

[tex] \sqrt{( \sqrt{} 3 {}^{2} } + 1 {}^{2} )[/tex]

[tex] \sqrt{4} = 2[/tex]

then the angle,

[tex] \tan( \alpha ) = - 1 \div \sqrt{3} = 330[/tex]

in radians,

[tex]11\pi \div 6[/tex]

hope this helps for the next questions

Answer:

add 8x to both sides

Step-by-step explanation:

5-8x<2x+3

first step, subtract 3 from both sides:

2-8x<2x

second step,?

2<?x

so you need to add 8x first

Answer: see below

Step-by-step explanation:

A) y has the smaller radius so this is the Minor Axis

B) y has the smaller radius so these are the CoVertices

C) x has the bigger radius so these are the Vertices

D) This is the Center of the ellipse.

F & G) These are the Foci (plural for Focus)

H) x has the bigger radius so this is the Major Axis

Answer:

Below

Step-by-step explanation:

Suppose that m and n are both even numbers.

So we can express them as the product of 2 and another number.

● n = 2×a

● m = 2×b

● m-n = 2b-2a

● m-n = 2(b-a)

m-n is an even number since it is divisible by 2.

■■■■■■■■■■■■■■■■■■■■■■■■■■

Suppose that both n and m are odd numbers.

● n = 2a+1

● m = 2b+1

● m-n = 2b+1-(2a+1)

● m-n = 2b+1-2a-1

● m-n = 2b-2a

● m-n = 2(b-a)

So m-n is even since it is divisible by 2.

■■■■■■■■■■■■■■■■■■■■■■■■■■

Suppose that m is odd and n is even ir vice versa

● n = 2a or n= 2a+1

● m = 2b+1 or m = 2b

● m-n = 2b+1-2a or m-n = 2b-2a-1

● m-n = 2(b-a) +1 or m-n = 2(b-a)-1

In both cases m-n isn't even.

■■■■■■■■■■■■■■■■■■■■■■■■■■

So m-n is even if and only if m and n are odd or m and are even

Answer:

Case 1

both m and n are even

Therefore m/2 and n/2 are integers

Then,

m-n

=2(m/2 - n/2)

Since m/2 and n/2 are integers

Then m/2 - n/2 will be an integer

Therefore,

m-n = 2(Z)

Where Z is an integer

Since 2 is a factor of m-n

Therefore m -n is even

Case 2

Both m and n are odd

m-n

= 2(½m - ½n)

When an odd number is divided by 2 it gives an integer and a remainder of 1

Therefore

½m = Y + ½

And

½n = Z + ½

Where Y and Z are integers

Then

m-n = 2(Y+½-Z-½)

= 2(Y-Z)

Y-Z will also be an integer

m-n= 2A

Therefore m-n is even

Case 3

One is odd and the other even

m-n = 2(m/2 - n/2)

Assume m is even and n is odd

From the discussions above

m-n = 2(Y - Z - ½)

m-n = 2(A - ½)

Hence m-n is not even because when is divided by two it doesn't give an integer.

Therefore for all integers m and n, m - n is even if, and only if, both m and n are even or both m and n are odd.

Answer:

∑(-1)^k/(2k+1)! (5x)^2k+1

From k = 1 to 3.

= -196.5

Step-by-step explanation:

Given

∑(-1)^k/(2k+1)! (5x)^2k+1

From k = 0 to infinity

The expression that includes all terms up to order 3 is:

∑(-1)^k/(2k+1)! (5x)^2k+1

From k = 0 to 3.

= 0 + (-1/2 × 5³) + (1/6 × 10^5) + (-1/5040 × 15^5)

= -125/2 + 100000/6 - 759375/5040

= -62.5 + 16.67 - 150.67

= - 196.5

Answer:

Kindly check explanation

Step-by-step explanation:

Taking a careful look at the graph above, the graph depicts that there is sizeable growth or increase in the rate of interest between 2008 to 2012. However, the actual increase in the rate of interest between 2008 - 2012 is (3.152% - 3.141%) = 0.011%. This change is very small compared to what is portrayed by the pictorial representation of the bar graph. This could be due to the scaling of the vertical axis which didn't start from 0, thereby exaggerating the increase in the actual rate of interest. It will thus mislead observers into thinking the increase is huge.

Answer:

d) F2 = -F1.

Step-by-step explanation:

According to Coulomb's law of forces on electrostatic charges, the force of attraction is proportional to the product of their charges, and inversely proportional to the square of their distance apart.

What this law means is that both particles will experience an equal amount of force on them, due to the presence of the other particle. This force is not just as a result of their individual charges, but as a result of the product of their charges. Also, the force is a vector quantity that must have a direction alongside its magnitude, and the force on the two particles will always act in opposite direction, be it repulsive or attractive.

Answer:

a =4,b=2, c=3

Step-by-step explanation:

Answer:

[tex]p = 2[/tex] if given vectors must be linearly independent.

Step-by-step explanation:

A linear combination is linearly dependent if and only if there is at least one coefficient equal to zero. If [tex]\vec u = (1,1,2)[/tex], [tex]\vec v = (1,p,5)[/tex] and [tex]\vec w = (5,3,4)[/tex], the linear combination is:

[tex]\alpha_{1}\cdot (1,1,2)+\alpha_{2}\cdot (1,p,5)+\alpha_{3}\cdot (5,3,4) =(0,0,0)[/tex]

In other words, the following system of equations must be satisfied:

[tex]\alpha_{1}+\alpha_{2}+5\cdot \alpha_{3}=0[/tex] (Eq. 1)

[tex]\alpha_{1}+p\cdot \alpha_{2}+3\cdot \alpha_{3}=0[/tex] (Eq. 2)

[tex]2\cdot \alpha_{1}+5\cdot \alpha_{2}+4\cdot \alpha_{3}=0[/tex] (Eq. 3)

By Eq. 1:

[tex]\alpha_{1} = -\alpha_{2}-5\cdot \alpha_{3}[/tex]

Eq. 1 in Eqs. 2-3:

[tex]-\alpha_{2}-5\cdot \alpha_{3}+p\cdot \alpha_{2}+3\cdot \alpha_{3}=0[/tex]

[tex]-2\cdot \alpha_{2}-10\cdot \alpha_{3}+5\cdot \alpha_{2}+4\cdot \alpha_{3}=0[/tex]

[tex](p-1)\cdot \alpha_{2}-2\cdot \alpha_{3}=0[/tex] (Eq. 2b)

[tex]3\cdot \alpha_{2}-6\cdot \alpha_{3} = 0[/tex] (Eq. 3b)

By Eq. 3b:

[tex]\alpha_{3} = \frac{1}{2}\cdot \alpha_{2}[/tex]

Eq. 3b in Eq. 2b:

[tex](p-2)\cdot \alpha_{2} = 0[/tex]

If [tex]p = 2[/tex] if given vectors must be linearly independent.

Answer:

2x

Step-by-step explanation:

These are like terms so we can combine them

4x-2x

2x

Answer:

2x

Explanation:

Since both terms in this equation are common, we can simply subtract them.

4x - 2x = ?

4x - 2x = 2x

Therefore, the correct answer should be 2x.

Answer:

b.28 its ans is no.b

Step-by-step explanation:

no point score in basketball

Answer:

[tex]V(m) = (2 + 5m)^3[/tex]

Step-by-step explanation:

Given

Solid Shape = Cube

Edge = 2 feet

Increment = 5 feet per minute

Required

Determine volume as a function of minute

From the question, we have that the edge of the cube increases in a minute by 5 feet

This implies that,the edge will increase by 5m feet in m minutes;

Hence,

[tex]New\ Edge = 2 + 5m[/tex]

Volume of a cube is calculated as thus;

[tex]Volume = Edge^3[/tex]

Substitute 2 + 5m for Edge

[tex]Volume = (2 + 5m)^3[/tex]

Represent Volume as a function of m

[tex]V(m) = (2 + 5m)^3[/tex]

The area is given by the integral

[tex]\displaystyle A=2\pi\int_Cx(t)\,\mathrm ds[/tex]

where C is the curve and [tex]dS[/tex] is the line element,

[tex]\mathrm ds=\sqrt{\left(\dfrac{\mathrm dx}{\mathrm dt}\right)^2+\left(\dfrac{\mathrm dy}{\mathrm dt}\right)^2}\,\mathrm dt[/tex]

We have

[tex]x(t)=t+\sqrt 2\implies\dfrac{\mathrm dx}{\mathrm dt}=1[/tex]

[tex]y(t)=\dfrac{t^2}2+\sqrt 2\,t+1\implies\dfrac{\mathrm dy}{\mathrm dt}=t+\sqrt 2[/tex]

[tex]\implies\mathrm ds=\sqrt{1^2+(t+\sqrt2)^2}\,\mathrm dt=\sqrt{t^2+2\sqrt2\,t+3}\,\mathrm dt[/tex]

So the area is

[tex]\displaystyle A=2\pi\int_{-\sqrt2}^{\sqrt2}(t+\sqrt 2)\sqrt{t^2+2\sqrt 2\,t+3}\,\mathrm dt[/tex]

Substitute [tex]u=t^2+2\sqrt2\,t+3[/tex] and [tex]\mathrm du=(2t+2\sqrt 2)\,\mathrm dt[/tex]:

[tex]\displaystyle A=\pi\int_1^9\sqrt u\,\mathrm du=\frac{2\pi}3u^{3/2}\bigg|_1^9=\frac{52\pi}3[/tex]

Answer:

$139.23

Step-by-step explanation:

50% off the original price of $239.99

= $239.99-(0.5*239.99)

= 239.99-119.995

= $119.995

She purchase a pair of shoes also worth $34.70

Total cost now= $119.995 + $34.70

Total cost now= $154.695

But she has a coupon that gives her 10% off her total sales

Now she wants pay

= $154.695 - 0.1(154.695)

= $154.695-15.4695

= $139.2255

Approximately $139.23

Answer:

Points : ( 8, - 2π/3 ), ( - 8, π/3 ), ( - 8, - 5π/3 )

Step-by-step explanation:

For the first two cases, ( r, θ ) r would be > 0, where r is the directed distance from the pole, and theta is the directed angle from the positive x - axis.

So when r is positive, we can tell that this point is 8 units from the pole, so r is going to be 8 in either case,

( 8, 240° ) - because r is positive, theta would have to be an angle with which it's terminal side passes through this point. As you can see that would be 2 / 3rd of 90 degrees more than a 180 degree angle,or 60 + 180 = 240 degrees.

( 8, - 120° ) - now theta will be the negative side of 360 - 240, or in other words - 120

Now let's consider the second two cases, where r is < 0. Of course the point will still be 8 units from the pole. Again for r < 0 the point will lay on the ray pointing in the opposite direction of the terminal side of theta.

( - 8, 60° ) - theta will now be 2 / 3rd of 90 degrees, or 60 degrees, for - r. Respectively the remaining degrees will be negative, 360 - 60 = 300, - 300. Thus our second point for - r will be ( - 8, - 300° )

_________________________________

So we have the points ( 8, 240° ), ( 8, - 120° ), ( - 8, 60° ), and ( - 8, - 300° ). However we only want 3 cases, so we have points ( 8, - 120° ), ( - 8, 60° ), and ( - 8, - 300° ). Let's convert the degrees into radians,

Points : ( 8, - 2π/3 ), ( - 8, π/3 ), ( - 8, - 5π/3 )