In 1980, the median age of the U.S. population was 30.0; in 2000, the median age was 35.3. Consider 1980 as the starting point (time zero) for this problem. Create an explicit exponential formula for the median age of the U.S. population t years after 1980, assuming the median age has exponential growth.

Answers

Answer 1

Answer: [tex]30e^{0.00813x}[/tex]

Step-by-step explanation:

Given

Median age in 1980 is [tex]30[/tex]

It is [tex]35.3[/tex] in year 2000

Suppose the median age follows the function [tex]ae^{bx}[/tex]. Consider 1980 as starting year. Write the equation for year 1980

[tex]\Rightarrow 30=ae^{b(0)}\\\Rightarrow 30=a[/tex]

For year 2000

[tex]\Rightarrow 35.3=30e^{20b}\\\\\Rightarrow \dfrac{30e^{20b}}{30}=\dfrac{35.3}{30}\\\\\Rightarrow e^{20b}=1.17666\\\\\Rightarrow b=0.00813[/tex]

After t years of 1980

[tex]\Rightarrow 30e^{0.00813x}[/tex]


Related Questions

Use the value of phi = 1.618 to predict the 23rd number in the Fibonacci sequence. The 22nd number in the sequence is 17,711.

- 10,946

- 17,711

- 22,897

- 28,656

Answers

Given:

[tex]\phi=1.618[/tex]

22nd number in Fibonacci sequence = 17,711

To find:

The 23rd number in the Fibonacci sequence.

Solution:

The nth term of a Fibonacci sequence is:

[tex]f_n=\dfrac{\phi^n-(1-\phi)^n}{\sqrt{5}}[/tex]

Substituting [tex]\phi=1.618, n=21[/tex], we get

[tex]f_{21}=\dfrac{(1.618)^{21}-(1-1.618)^{21}}{\sqrt{5}}[/tex]

[tex]f_{21}=\dfrac{(1.618)^{21}-(1-1.618)^{21}}{\sqrt{5}}[/tex]

[tex]f_{21}=10941.1724024[/tex]

[tex]f_{21}\approx 10941[/tex]

Now,

[tex]f_{23}=f_{21}+f_{22}[/tex]

[tex]f_{23}=10941+17711[/tex]

[tex]f_{23}=28652[/tex]

It is about 28,656. Therefore, the correct option is D.

Which rule describes the transformation shown?

1. (x,y) → (-y, x+7)

2. (x,y) → (x+7,-y)

3. (x,y) → (-x, y+7)

4. (x,y) → (y+7, -x)

Answers

Answer:

2. (x,y) → (x+7,-y)

Step-by-step explanation:

Point A:

The original coordinate of point A was (-6,-6).

The coordinate after the transformation is A'(1,6), which eliminates option 3.

Point B:

The original coordinate of point B was (-2,4).

After the transformation, we have B'(5,-4), which eliminates option 1 and option 4. This means that the correct answer is:

2. (x,y) → (x+7,-y)

What is the value of x if x/ 3 + 1 = -2 ?​

Answers

Answer:x = -9

Step-by-step explanation:

Step 1: Simplify both sides of the equation.1/3x+1=−2Step 2: Subtract 1 from both sides.1/3x+1−1=−2−11/3x=−3Step 3: Multiply both sides by 3.3*(1/3x)=(3)*(−3)x=−9

Please help!!!!
I’m using Plato

Answers

1 by 4 ^ 256 is equal to 4 and 1 by 4 ^ 64 will be root 4 so here the answer will be 4 into 4 root 4

there option 4 will be correct

GM projected that 3% of their cars produced this year will be defective. If GM produced 1,698 cars that were defective, how many cars did GM produce this year

Answers

Answer:

56600 cars

Step-by-step explanation:

Below is the calculation of number of cars produced.

The percentage of cars that is defected = 3%

Number of cars that are defective = 1698 cars

The number of cars produced in a year = 1698 / 3%  

The number of cars produced in a year = 56600 cars

A board is 87 cm in length and must be cut so that one piece is 21 cm longer than the other piece. Find the length of each piece. Round your answers to the nearest centimeter, if necessary. * + 21?​

Answers

Thank you for answer Yey can I answer in my subject

Please help will mark brainliest!

Answers

Answer:

  (d) ∠B≅∠D

Step-by-step explanation:

The last statement of any proof is a restatement of what is being proven. Here, that is ...

  ∠B≅∠D

What is the depth of water in a tank with 300,000 gallons of water at 70F when the pressure gauge at the bottom of the tank reads 23 psig?​

Answers

Answer:

53.08 ft

Step-by-step explanation:

The pressure at the bottom of the tank, P = ρgh where ρ = density of water = 1000 kg/m³, g = acceleration due to gravity = 9.8 m/s² and h = depth of water in tank.

Since the pressure at the bottom of the tank, P = ρgh, making h subject of the formula, we have

h = P/ρg

Since P = 23 psig = 23 × 1 psig = 23 × 6894.76 Pa = 158579.48 Pa

Substituting the values of the other variables into h, we have

h = P/ρg

h = 158579.48 Pa/(1000 kg/m³ × 9.8 m/s²)

h = 158579.48 Pa/(9800 kg/m²s²)

h = 16.18 m

h = 16.18 × 1 m

h = 16.18 × 3.28 ft

h = 53.08 ft

The population of watesville decreases at a rate of 1.6% each year if the population was 62,500 in 2015 what will it be in 2021

Answers

Answer:

Step-by-step explanation:

We need to first find the model for this particular situation, knowing that this is an exponential decay problem. The main equation for exponential growth/decay (as far as population goes for our problem) is

[tex]y=a(b)^x[/tex] where a is the initial population, b is the rate of decrease in the population which can also be written as (1 - r), y is the population after a certain amount of time, x, goes by. We will let year 2015 = 0 so year 2021 can = 6. This keeps our numbers lower and doesn't change the answer!

Our initial population in the year x = 0 is 62500. Our rate of decay is

(1 - .016) so our b value is .984

Filling in to find our model:

[tex]y=62500(.984)^x[/tex]

Now we can use that model and sub in a 6 for x to find the population in the year 2021:

[tex]y=62500(.984)^6[/tex] and

y = 62500(.9077590568) so

y = 56734.9 or, rounded to the nearest person, 56735

The product of -3x and (2x+5) is …​

Answers

[tex]\huge{\boxed{\boxed{ Solution ⎇}}} \ [/tex]

[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x[/tex]

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ ツ

꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐

[tex] \huge\boxed{\mathfrak{Answer}}[/tex]

[tex] - 3x \times (2x + 5) \\ = - 3x \times 2x + - 3x \times 5 \\ = - 6x ^{2} - 15x [/tex]

Answer ⟶ - 6 - 15x

8/9 - 1/3
Very easy question for 10 pts

Answers

Answer:

answer is 5/9

Step-by-step explanation:

Answer:

The answer is 5/9 or 0.555 (the 5 is repeated)

What is the y-intercept of the graph of y = 2.5x? a. 2.5 c. 0 b. 1 d. -1

Answers

Answer:

answer is C

Step-by-step explanation:

General equation of a line is expressed as shown:

y = mx+c where;

m is the slope or gradient of the line

c is the intercept of the line

Given the equation of the line graph as y =2.5x

Comparing the given equation with the general equation, it is seen that m = 2.5 and c = 0 (since there is no value for the intercept)

Based on the explanation, the y-intercept of the graph is therefore 0

Answer:

B

Step-by-step explanation:

To find the x-intercept, substitute in

0 for y and solve for x

To find the y-intercept, substitute in 0 for x and solve for y

x-intercept(s): None

y-intercept(s): (0,1)

The number of measles cases increased 26.3% to 321 cases this year. What was the number of cases prior to the increase? Express your answer rounded correctly to the nearest whole number.

Answers

Answer:

The right answer is "[tex]x\simeq 254[/tex]".

Step-by-step explanation:

Let the number of earlier case will be "x".

Now,

⇒ [tex]x+x\times \frac{26.3}{100}=321[/tex]

or,

⇒ [tex]x+x\times 0.263=321[/tex]

By taking "x" common, we get

⇒   [tex]x(1+0.263)=321[/tex]

⇒                    [tex]x=\frac{321}{1.263}[/tex]

⇒                       [tex]=254.15[/tex]

or,

⇒                    [tex]x\simeq 254[/tex]

X is less than or equal to 2 Write in interval notation.

Answers

x is less than -2, so -2 is our largest value of the interval, so it goes on the right. Since there is no lower endpoint (it is ALL values less than -2), we put the negative infinity symbol on the left side. The curved end on -2 indicates an open interval

Round 1001 to the nearest thousand.

Answers

1000 is the correct answer !

Barry and Robin walk to Dunkin' Donuts each Saturday to meet for coffee and donuts. Barry walks the 2 miles from his house in 30 minutes and Robin walks the 3 miles from his house in 36 minutes. Find the unit rate in minutes per mile for Barry. Find the unit rate in minutes per mile for Robin. Who walks faster, Barry or Robin

Answers

Answer : barry

12<15

Barry's unit rate is 15 minutes per mile and Robin's unit rate is 12 minutes per mile

The unit rates of Barry and Robin

We have:

Barry

Distance = 2 miles

Time = 30 minutes

Unit rate = Time/Distance

Unit rate = 30 minutes/2 miles

Unit rate = 15 minutes per mile

Robin

Distance = 3 miles

Time = 36 minutes

Unit rate = Time/Distance

Unit rate = 36 minutes/3 miles

Unit rate = 12 minutes per mile

Hence, Barry's unit rate is 15 minutes per mile and Robin's unit rate is 12 minutes per mile

Who walk faster?

The unit rates mean that:

Barry covers 1 mile in 15 minutesRobin covers 1 mile in 12 minutes

Hence, Robin walks faster

Read more about unit rates at:https://brainly.com/question/19493296

#SPJ6


Keiko, Chang, and Abdul sent a total of 109 text messages over their cell phones during the weekend. Keiko sent 7 fewer messages than Chang. Abdul sent 4
times as many messages as Keiko. How many messages did they each send?

Answers

9514 1404 393

Answer:

Keiko: 17Chang: 24Abdul: 68

Step-by-step explanation:

Let c represent the number of messages sent by Chang. Then Keiko sent (c-7) messages, and Abdul sent 4(c-7) messages. The total number sent was ...

  c + (c -7) +4(c -7) = 109

  6c -35 = 109 . . . . . . . . . . simplify

  6c = 144 . . . . . . . . . . . add 35

  c = 24 . . . . . . . . . . . divide by 6

  c-7 = 17

  4(c-7) = 68

Keiko sent 17, Chang sent 24, and Abdul sent 68 text messages.

Kaitlin is riding her bike. The number of revolutions (turns) her wheels make varies directly with the distance she travels. See the graph below.



How far does Kaitlin travel per revolution?

What is the slope of the graph?

Answers

Answer:

m = Δy/Δx = 4/32 = 1/8

8 ft/rev.

Step-by-step explanation:

Answer:

[tex]\frac{1}{8}[/tex] for both

Step-by-step explanation:

1. Distance per revolution

We see that the distance travelled at 2 revolutions is 16

This means that she travels [tex]\frac{1}{8}[/tex] of a mile per revolution

2. Slope

The slope formula is rise/run, or ([tex]y[/tex]₂[tex]-y[/tex]₁)/([tex]x[/tex]₂[tex]-x[/tex]₁)

We can take two points, (16,2) and (32,4)

[tex]\frac{4-2}{32-16}=\frac{2}{16}=\frac{1}{8}[/tex]

The slope is [tex]\frac{1}{8}[/tex]

Hope this helps! Please mark brainliest :)

An equation, f, has a domain of all whole numbers and has a range of all real numbers. A) Does the equation
represent a function? B) Explain why or why not. C) provide examples in either case, (and include your reasoning why
you chose this equation for your example.)

Answers

Answer:

f is not a function

Step-by-step explanation:

Given

Domain: Whole numbers

Range: Real numbers

Required

Is f a function

Base on the given parameters, f is not a function because:

There are more real numbers than whole numbers

And this implies that at least one element in the domain will have more than one corresponding elements in the range. i.e. one-to-many or many-to-many relationship

For a relation to be regarded as a function, the relationship has to be one-to-one or many-to-one

i.e. 1 or many domain elements to 1 element in the range.

An example is:

[tex]\begin{array}{ccccc}x & {1} & {9} & {9} & {0} \ \\ f(x) & {1.5} & {3.2} & {-3.5} & {0.1} \ \end{array}[/tex]

In the above function

The domain (i.e. x values) are whole numbers

The range (i.e. y values) are real numbers

However,

9 points to 3.2 and -3.5

So, the relation is not a function.

Skylar's grades on four math tests are 85, 78, 77, and 69. What does Skylar need to score on the next test in order to have a mean score of 80?

Answers

Answer:

91

Step-by-step explanation:

The mean the the average of 5 numbers. If the next score is x, then the mean is:

(85 + 78 + 77 + 69 + x)/5 = 80

Solve it for x:

309 + x = 80*5x = 400 - 309x = 91

It is given that,

The mean is the average of 5 numbers.

Then if the,

Next score is x the mean will be.

We can solve now,

→ (85 +78 +77 + 69 + x)/5 = 80

→ (309 + x)/5 = 80

→ 309 + x = 80 × 5

→ 309 + x = 400

→ x = 400 - 309

→ x = 91

Hence, the next score is 91.

what are the missing numbers ?

Answers

It is d 5,6,8,9
Cube root 8 is 2 + 7 is 9

(a^2 - b^2)=???????????????????????????

Answers

[tex](a^2 - b^2) = (a + b)(a - b)[/tex]

find the x-intercepts y=2x^2 + 5x + 2/x^2-4x+3

Answers

Answer:

[tex]{ \tt{y = \frac{2 {x}^{2} + 5x + 2}{ {x}^{2} - 4x + 3 } }} \\ x - intercept : y = 0 \\ { \tt{ \frac{2 {x}^{2} + 5x + 2 }{ {x}^{2} - 4x + 3 } = 0 }} \\ \\ { \tt{2 {x}^{2} + 5x + 2 = 0}} \\ x = \frac{1}{2} \: \: and \: \: x = - 2[/tex]

suppose △abc≅△xyz. what is the corresponding congruent part for each segment or angle?​

Answers

Answer:

Step-by-step explanation:

Mr johnson sells erasers for $3 each. He sold 96 erasers last week and he sold 204 erasers this week.

A. $300 B $600 C $100 D $900

Answers

I believe your answer is D.) $900

204 + 96 = 300

300 x 3 = 900

I hope this is correct and helps!

I only need the odd numbers answered

Answers

Answer:

1.a+4=11

a=7

2.6=g+8

g=2

3.

?

4.k+8=3

k=-5

5.j+0=9

j=9

6.12+y=15

y=3

7.h-4=0

h=4

8.m-7=1

m=8

9.w+5=4

w=-2

10.b-28=33

b=61

11.45+f=48

f=3

12.n+7.1=8.6

n=1.5

Hope This Helps!!!

If (3x − 2)(3x + 2) = ax2 − b, what is the value of a?

Answers

(3x-2)(3x+ 2)

Multiply each term in one set of parentheses by the other terms:

3x x 3x =9x^2

3x x 2 = 6x

-2 x 3x = -6x

-2 x 2 = -4

Combine to get:

9x^2 + 6x - 6x -4

Combine like terms:

9x^2 - 4

The value of a would be 9.

[tex]\sf{\bold{\blue{\underline{\underline{Given}}}}}[/tex]

(3x − 2)(3x + 2) = ax2 − b⠀⠀⠀⠀

[tex]\sf{\bold{\red{\underline{\underline{To\:Find}}}}}[/tex]

⠀what is the value of a?⠀⠀⠀

[tex]\sf{\bold{\purple{\underline{\underline{Solution}}}}}[/tex]

At first we have to solve the value of (3x-2)(3x+2)

[tex]\sf{(3x-2)(3x+2) }[/tex]

[tex]\sf{3x(3x+2)-2(3x+2) }[/tex]

[tex]\sf{9x^{2}+6x-6x-4 }[/tex]

[tex]\sf{9x^{2}-4 }[/tex]

According to the question,

[tex]\sf{ (3x − 2)(3x + 2) = ax^{2} − b }[/tex]

[tex]\sf{9x^{2}-4=ax^{2}-b }[/tex]

[tex]\sf{9x^{2}=ax^{2}~and~-4=-b }[/tex]

[tex]\sf{a=9~and~b=4 }[/tex]

⠀⠀⠀

[tex]\sf{\bold{\green{\underline{\underline{Answer}}}}}[/tex]

Hence,

The value of a is 9

I have no idea how to do this, so if someone could at least do one of these I’ll be grateful <3

Answers

Answer:

Answers are below!

Step-by-step explanation:

(2 + g) (8)

= (2 + g) (8)

Add a 8 after the 2, and flip.

= (2)(8) + (g)(8)

= 16 + 8g

= 8g + 16

= (4) (8 + -5g)

Add another 4, then flip.

= (4) (8) + (4) (-5g)

= 32 − 20g

= - 20g + 32

−7 (5-n)

= (−7) (5 + -n)

Add another 7, then flip.

= (−7) (5) + (-7) (-n)

= −35 + 7n

= 7n - 35

Use the distributive property.

a (b + c) = ab + ac

a = 8

b = 2m

c = 1

= 8 × 2m + 8 × 1

Simplify, you get 16m + 8.

Use the distributive property.

a (b + c) = ab + ac

a = 6x

b = y

c = z

= 6xy - 6xz is the answer.

[tex]\mathrm{Apply\:the\:distributive\:law}:\quad \\\:a\left(b+c\right)=ab+ac[/tex]

[tex]a=-3,\:b=2b,\:c=2a[/tex]

[tex]=-3\cdot \:2b+\left(-3\right)\cdot \:2a[/tex]

Apply minus plus rules.

[tex]=-3\cdot \:2b+\left(-3\right)\cdot \:2a[/tex]

Multiply the numbers.

3 x 2 = 6

Answer:

9. -35+7n

10. 16m+8

11. 6xy-6xz

Step-by-step explanation:

You multiplying the terms inside the ( ) by the outside factor.

This is call distributive property, a(b+c)=ab+ac.

Also, a(b+c)=(b+c)a by commutative property.

It also works over the operation subtraction since subtraction is just a disguised addition (addition of the opposite). That is, a(b-c)=ab-ac.

Anyhow, let's look at 9.,10., and 11..

9.

-7(5-n)

(-7)(5-n)

(-7)(5)-(-7)(n)

-35+7n

10.

8(2m+1)

(8)(2m)+(8)(1)

16m+8

11.

6x(y-z)

(6x)(y-z)

(6x)(y)-(6x)(z)

6xy-6xz

Hint on 7. It's like all the other problems. That is, it is equivalent to doing 8(2+g).

If you want comment below, if you want me to check any of yours or if you have any questions.

PLS HELP QUICK I WILL GIVE YOU BRAINLIEST:

Given that angle abc=70° and angle bcd=110°. Is it possible (consider all cases): That line AB intersects line CD?

Answers

Answer:

Given that angle abc = 70° and angle bcd = 110°. Is it possible (consider all cases): That line AB intersects line CD?

yes.

Step-by-step explanation:

#CarryOnLearning

Consider the quadratic function y = 0.3 (x-4)2 - 2.5
Determine the axis of symmetry, x =

Answers

Answer:

[tex]x=4[/tex]

Step-by-step explanation:

We have the quadratic function:

[tex]\displaystyle y=0.3(x-4)^2-2.5[/tex]

And we want to determine its axis of symmetry.

Notice that this is in vertex form:

[tex]y=a(x-h)^2+k[/tex]

Where (h, k) is the vertex of the parabola.

From our function, we can see that h = 4 and k = -2.5. Hence, our vertex is the point (4, -2.5).

The axis of symmetry is equivalent to the x-coordinate of the vertex.

The x-coordinate of the vertex is 4.

Therefore, the axis of symmetry is x = 4.

Other Questions
Physics help please What did entertainment during theGreat Depression emphasize? Write an expression that evaluates to True if the string associated with s1 is greater than the string associated with s2 Zeitoun went outside, the air humid and gusty. He tied the canoe to the back porch. The water was whispering through the cracks in the back fence, rising up. It was flowing into his yard at an astonishing rate. As he stood, it swallowed his ankles and crawled up his shins. Back inside, he continued to move everything of value upward. As he did, he watched the water erase the floor and climb the walls. In another hour there was three feet of water indoors. And his house was three feet above street level. What conclusion can readers draw about this character vs. nature conflict How many marbles do you need to be able to arrange them into the shape of an equilateral triangle with 75 rows Exercise 4-10 Preparing adjusting and closing entries for a merchandiser LO P3 The following list includes selected permanent accounts and all of the temporary accounts from the December 31 unadjusted trial balance of Emiko Co., a business owned by Kumi Emiko. Emiko Co. uses a perpetual inventory system. Debit Credit Merchandise inventory $ 40,000 Prepaid selling expenses 7,600 Dividends 53,000 Sales $ 609,000 Sales returns and allowances 21,500 Sales discounts 7,000 Cost of goods sold 252,000 Sales salaries expense 68,000 Utilities expense 25,000 Selling expenses 46,000 Administrative expenses 125,000 Additional Information Accrued and unpaid sales salaries amount to $1,800. Prepaid selling expenses of $2,900 have expired. A physical count of year-end merchandise inventory is taken to determine shrinkage and shows $34,700 of goods still available. (a) Use the above account balances along with the additional information, prepare the adjusting entries. (b) Use the above account balances along with the additional information, prepare the closing entries. Self-esteem and loss of control are keyfactors of our mental well being.A-TrueB-False When Maria suggests a product modification to a supplier of her company, she is performing which of these roles according to Mintzberg? what is photo synthesis Write the ratio 4 3/5 to 1 1/5 as a fraction in lowest terms Tracey Sales Co. has predicted the following costs for this year for 500,000 units: Manufacturing Selling and Administrative Variable $ 800,000 $250,000 Fixed 1,200,000 300,000 Total $2,000,000 $550,000 What is the markup on variable manufacturing costs needed to break even Is sociology a science or an art? How can sociology be defined as a science AND an art? Light dependent reactions are carried out both on and in between photosystems. This process is like the last stage of aerobic respiration in that both:______.a. reaction sequences carry out electron transfer phosphorylations.b. processes generate ATP.c. processes involve electron flow.d. systems are lodged along and within a membrane surface. e. all of the above. How did Emperor Theodosius become a convert and stopped persecution You own a small storefront retail business and are interested in determining the average amount of money a typical customer spends per visit to your store. You take a random sample over the course of a month for 12 customers and find that the average dollar amount spent per transaction per customer is $116.194 with a standard deviation of $11.3781. Create a 90% confidence interval for the true average spent for all customers per transaction.1) ( 114.398 , 117.99 )2) ( 112.909 , 119.479 )3) ( -110.295 , 122.093 )4) ( 110.341 , 122.047 )5) ( 110.295 , 122.093 ) help pls, stuck on this HELP PLEASE!!!!!!!!!!!!!!! A professor is interested in whether or not college students have a preference (indicated by a satisfaction score) for reading a textbook that has a layout of one column or layout of two columns. In the above experiment, what is the dependent variable On dividing 12x by 4x the quotient is .. Find in the triangle. Round to the nearest degree.