In a population of 400,000 people, 160,000 are infected with a virus. After a person becomes infected and then recovers, the person is immune (cannot become infected again). Of the people who are infected, 4% will die each year and the others will recover. Of the people who have never been infected, 15% will become infected each year. How many people will be infected in 4 years

Answer:

2528839

Step-by-step explanation:

your welcome

Answer:

y = (1/4) 2^x

Step-by-step explanation:

Remark

y = a * x^n is the general equation. Let's see what that means.

Solution

Solve for x

t_12 = a x^12

1024 = a x^12

t_8 = a x^8

64 = a x^8

Now divide the two equations.

1024/64 = a x^12/a x^8       Cancel out the as

1024 / 64 = x^12 / x^8

16 = x^(12 - 8)

16 = x^4                               Take the 4th root of both sides.

[tex]\sqrt[4]{x^4}[/tex]  =  [tex]\sqrt[4]{16}[/tex]

x = 2

Go back and solve for a

y_12 = a x^12

1024 = a 2^12

1024 = a 4096                   Divide by 4096

1024 / 4096 = a

a = 1/4

Problem 7

a) First of negative numbers are probably not a good idea. It means that the population is going to decrease. That's not what will happen if you take care of the fruit flies.

So for the domain, 0 is a good starting point.

That will give you 100 flies on day 0. That's how many you bought.

I'm not a biologist so I have no idea in the world how long a fruit fly will live even with the best of care. I'm going to try 60 days and see what happens.

y = 100 * 1.05 ^60

y = 100 * 18.68

y = 1868

Is this number reasonable? Even with the biggest olive jar you can find, and the best care, I don't think that number is realistic. It's too large. Eventually all will die of disease because they are living in their own waste. So Let's try 20 days

y = 100 * 1.05^20

y = 100 * 2.65

y = 265

That's a lot more reasonable. So for convenience sake let us say that 265 flies could live for 20 days

So to answer the question

The domain would be 0 to 20

The range would be 100 to 265

b)

2 weeks = 2*7 days

2 weeks = 14 days

y = 100 * 1.05^14

y = 100 * 1.98

y = 198 fruit flies.

Answer:

He completes a lap running in 3 minutes, and walking in 4 minutes.

Step-by-step explanation:

This question can be solved by a system of equations.

I am going to say that:

x is the time needed to complete a lap running.

y is the time needed to complete a lap walking.

He requires 40 minutes to do 4 laps running and 7 laps walking.

This means that:

[tex]4x + 7y = 40[/tex]

[tex]4x = 40 - 7y[/tex]

He requires 18 minutes to do 2 laps running and 3 laps walking.

This means that

[tex]2x + 3y = 18[/tex]

Multipluing everything by 2

[tex]4x + 6y = 36[/tex]

Since [tex]4x = 40 - 7y[/tex]

[tex]40 - 7y + 6y = 36[/tex]

[tex]y = 4[/tex]

And

[tex]4x = 40 - 7y[/tex]

[tex]4x = 40 - 7*4[/tex]

[tex]4x = 12[/tex]

[tex]x = \frac{12}{4}[/tex]

[tex]x = 3[/tex]

He completes a lap running in 3 minutes, and walking in 4 minutes.

Answer:

[tex]\bar x =2.53[/tex] -- Mean

[tex]Median= 2[/tex]

[tex]Mode = 2[/tex]

[tex]Range = 8[/tex]

[tex]Q_1 = 1[/tex]

[tex]Q_3 = 3[/tex]

[tex]IQR = 2[/tex]

Step-by-step explanation:

Given

n = 30

Data: 2 3 1 2 6 4 2 1 5 3 2 3 1 2 2 1 3 1 2 2 4 2 1 2 9 3 2 1 1 3

Solving (a): The mean

This is calculated as:

[tex]\bar x =\frac{\sum x}{n}[/tex]

[tex]\bar x =\frac{2 +3 +1 +2 +6 +4 +2 +1 +5 +3 +2 +3+ 1+ 2 +2 +1 +3 +1 +2 +2 +4 +2 +1 +2 +9 +3 +2 +1 +1 +3}{30}[/tex]

[tex]\bar x =\frac{76}{30}[/tex]

[tex]\bar x =2.53[/tex]

Solving (b): The median

First arrange the given data

Arranged: 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 4 4 5 6 9

[tex]Median =\frac{1}{2}(n+1)[/tex]

[tex]Median =\frac{1}{2}(30+1)[/tex]

[tex]Median =\frac{1}{2}(31)[/tex]

[tex]Median = 15.5th[/tex]

This implies that the median is the average of the 15th and 16th item

[tex]Median = \frac{2+2}{2}[/tex]

[tex]Median = \frac{4}{2}[/tex]

[tex]Median= 2[/tex]

Solving (c): The mode

From the given data; 2 has the highest frequency of 11.

So,

[tex]Mode = 2[/tex]

Solving (d): The Range

[tex]Range = Highest\ Data - Lowest\ Data[/tex]

The highest is 9 and the lowest is 1,

So:

[tex]Range = 9 - 1[/tex]

[tex]Range = 8[/tex]

Solving (e): Lower (Q1) and Upper (Q3) quartile.

Q1 is calculated as:

[tex]Q_1 = \frac{1}{4}(n+1)th[/tex]

[tex]Q_1 = \frac{1}{4}(30+1)th[/tex]

[tex]Q_1 = \frac{1}{4}(31)th[/tex]

[tex]Q_1 = 7.75th[/tex]

[tex]Q_1 = 8th\ item[/tex]

[tex]Q_1 = 1[/tex] -- from the arranged data

Q3 is calculated as:

[tex]Q_3 = \frac{3}{4}(n+1)th[/tex]

[tex]Q_3 = \frac{3}{4}(30+1)th[/tex]

[tex]Q_3 = \frac{3}{4}(31)th[/tex]

[tex]Q_3 = 23.25th[/tex]

[tex]Q_3 = 23rd\ item[/tex]

[tex]Q_3 = 3[/tex] -- from the arranged data

Solving (f): The interquartile range (IQR)

[tex]IQR = Q_3 - Q_1[/tex]

[tex]IQR = 3-1[/tex]

[tex]IQR = 2[/tex]

Answer:

X= -6

Step-by-step explanation:

7x = -42

(÷7) (÷7)

X = -6

Answer:

Not sure if that is "9x" or "9 times" but I will do both. I have attached a picture of me solving and explaining the steps. Hope this helps, thank you !!

Answer:

I chose a box of cereal-------> rectangular prism

see the attached figure

Part 1)List the dimensions of your box. Be sure to include the units (in, cm, ft, etc.).

Length: 20 cm

Width: 8 cm

Height: 32 cm

Part 2).

Describe the shape of the cross-section when the box is cut parallel to the base

the shape of the cross-section would be a rectangle of dimensions

20 cm x 8 cm

Part 3)

What is the surface area of the box?

surface area=2*area of the base+perimeter of the base*height

area of the base=20*8=160 cm²

perimeter of the base=2*[20+8]-----> 56 cm

height=32 cm

surface area=2*160+56*32------> 2,112 cm²

the answer part 3) is

2,112 cm²

Part 4)

What is the surface area of the box if it is scaled up by a factor of 10?

we know that

surface area of the larger box=[scale factor]²*surface area original box

scale factor=10

surface area original box=2,112 cm²

so

surface area of the larger box=10²*2,112-----> 211,200 cm²

the answer part 4) is

211,200 cm²

Part 5)

What is the volume of the box?

volume of the box=L*W*H-----> 20*8*32------> 5,120 cm³

the answer Part 5) is

5,120 cm³

Part 6)

What is the volume of the box if it is scaled down by a factor of 1/10

we know that

volume of the smaller box=[scale factor]³*volume original box

scale factor=1/10

volume original box=5,120 cm³

so

volume of the smaller box=[1/10]³*5,120-----> 5.12 cm³

the answer part 6) is

5.12 cm³

Step-by-step explanation:

Answer:

541/2 square

Step-by-step explanation:

we know that

the volume of the smaller box=[scale factor]³*volume original box

scale factor=1/10

volume original box=5,120 cm³

so

volume of the smaller box=[1/10]³*5,120-----> 5.12 cm³

the answer part 6) is 541/2 square

Answer:

3X=15

X=5

2X5= 10

G=10

Step-by-step explanation:

Answer:

The control group is the group that takes the sugar pill

Step-by-step explanation:

In drug testing, to determine the efficacy of a drug, different groups of experimental subjects are recruited, one group is given the drug to be tested (treatment group) while another group is given a placebo.

A placebo is a fake version of the drug to be tested that does not have any therapeutic effect on the test subjects that receive it. In this case, the control group receives the placebo which is the sugar pill. They serve as the baseline of measurement when the outcome of the effect of the drug testing is done. The groups that received the actual drugs are compared against the groups that received the hoax treatment, and any change occuring  in the test subjects become the changes occuring as a result of the test drug used, when the observations on the control group has been ruled out.

Answer:

(4 × 9) / 2 = 36/2 = 18 gitu yaaa

Answer:

18

Step-by-step explanation:

plug in r and s

4(9)/2

36/2

18

Answer:

[tex]\frac{x - 20}{ x^2 + x - 20} = \frac{5}{9(x-4)}+\frac{4}{(x+5)}[/tex]

Step-by-step explanation:

Given

[tex]\frac{x - 20}{ x^2 + x - 20}[/tex]

Required

Decompose into partial fraction

Start by factorizing the denominator:

[tex]x^2 + x - 20 =x^2 + 5x -4x- 20[/tex]

[tex]x^2 + x - 20 =x(x + 5)-4(x+5)[/tex]

[tex]x^2 + x - 20 =(x-4)(x+5)[/tex]

So, we have:

[tex]\frac{x - 20}{ x^2 + x - 20} = \frac{A}{x-4}+\frac{B}{x+5}[/tex]

Take LCM

[tex]\frac{x - 20}{ x^2 + x - 20} = \frac{A(x+5)+B(x-4)}{(x-4)(x+5)}[/tex]

Cancel out the denominator

[tex]x - 20 = A(x+5)+B(x-4)}[/tex]

Open brackets

[tex]x - 20 = Ax+5A+Bx-4B[/tex]

Collect Like Terms

[tex]x - 20 = Ax+Bx+5A-4B[/tex]

[tex]x - 20 = (A+B)x+5A-4B[/tex]

By comparison;

[tex](A +B)x = x[/tex] ==>[tex]A + B = 1[/tex]

[tex]5A - 4B = 1[/tex]

Make A the subject in [tex]A + B = 1[/tex]

[tex]A = 1 - B[/tex]

Substitute 1 - B for A in [tex]5A - 4B = 1[/tex]

[tex]5(1-B) -4B = 1[/tex]

[tex]5-5B -4B = 1[/tex]

[tex]5-9B = 1[/tex]

Collect Like Terms

[tex]-9B = 1 - 5[/tex]

[tex]-9B = - 4[/tex]

[tex]B = \frac{4}{9}[/tex]

[tex]A = 1 - B[/tex]

[tex]A = 1 - \frac{4}{9}[/tex]

[tex]A = \frac{9-4}{9}[/tex]

[tex]A = \frac{5}{9}[/tex]

So:

[tex]\frac{x - 20}{ x^2 + x - 20} = \frac{A}{x-4}+\frac{B}{x+5}[/tex]

[tex]\frac{x - 20}{ x^2 + x - 20} = \frac{5}{9(x-4)}+\frac{4}{(x+5)}[/tex]

#First find the gradient first, remember that the formula of equation of the line is y = mx + c and gradient's symbol is m

y = ½x - 3

#so the gradient is ½, now u can find the equation of the lime.

y - y1 = m(x - x1)

y - 4 = ½(x - 6)

y - 4 = ½x - 3

y = ½x - 3 + 4

y = ½x + 1

Step-by-step explanation:

3cos2x +sinx=1

3(1-2sin²x)+sinx=1

3-6sin²x+sinx=1

sinx(-6sinx+1)=1

either

sinx=1

sinx=sin(90)

:.x=90

or

-6sinx+1=1

-6sinx=1-1

sinx=0/-6

sinx=sin0,sin180

:.x=0,180and90

Answer:

(6, -4)? is this on khan academy or smth

Step-by-step explanation:

Step-by-step explanation:

ssshzvecucsussddyz wksoav

Answer:

X=6 To y=-6

y=-4 TO X = 4

꧁꧁꧁꧁꧂꧂꧂꧂

꧂꧂꧂꧂꧂

Answer:

Boy I'm really boutta get to yo pickle chin ahh boy, egg head like collard greens head a//ss boy, oh hell nah boy yo dirt ahh boy stank ahh boy afro head ahh, lip gloss chin ahh boy ugly ahh boi

Step-by-step explanation:

Aawdadakdaw da  awdwa dadeefdcdcs

Answer:

Step-by-step explanation:

The amount of money that Ms. Gonzalez spends on small folders than large folders will be $12.75.

The allocation of weights to the important variables that produce the calculation's optimum is referred to as a direct consequence.

Ms. Gonzalez buys folders for her office. She buys 4 small folders for every 1 large folder. She buys 15 folders in all. Small folders cost $0.75, and large folders cost $1.25.

Let 'x' be the number of small folders and 'y' be the large folders. Then the equations are given as,

x + y = 15          ...1

y = 4x              ...2

From equations 1 and 2, then we have

x + 4x = 15

5x = 15

x = 3

Then the value of 'y' is given as,

3 + y = 15

y = 12

The cost of the small folder is given as,

⇒ $0.75 × 3

⇒ $2.25

The cost of the large folder is given as,

⇒ $1.25 × 12

⇒ $15

The difference is given as,

⇒ $15 - $2.25

⇒ $12.75

The amount of money that Ms. Gonzalez spends on small folders than large folders will be $12.75.

More about the solution of the equation link is given below.

https://brainly.com/question/545403

#SPJ5

Answer:

[tex]\frac{1}{5}[/tex] = [tex]\frac{2}{10}[/tex] = [tex]\frac{20}{100}[/tex]

Step-by-step explanation:

It's all about equivalent fractions.

[tex]\frac{1}{5}[/tex]

[tex]\frac{2}{10}[/tex]

[tex]\frac{20}{100}[/tex]

[tex]\frac{1}{5}[/tex] 1 × 2 = 2. 5 × 2 = 10. That is what makes [tex]\frac{2}{10}[/tex].

[tex]\frac{2}{10}[/tex] 2 × 10 = 20. 10 × 10 = 100. That is what makes [tex]\frac{20}{100}[/tex].

Answer:

4 hours

Step-by-step explanation:

Answer:

the answer of this question is

c

Answer:

4kg=4m/s

8kg=?

3m/s

Step-by-step explanation:

12kgm/s/4kg

Answer: Sorry I don't know

Step-by-step explanation:

Answer:

Step-by-step explanation:

Equation of a line  representing the relation between distance from the peak of the mountain and time is,

h = mt + b

Here, m = Slope of the line

b = y-intercept

Since, slope of the line passing through two points [tex](x_1,y_1)[/tex] and [tex](x_2,y_2)[/tex] is given by,

m = [tex]\frac{y_2-y_1}{x_2-x_1}[/tex]

From the table attached,

Slope of the line passing through (2, 2600) and (5, 950) will be,

m = [tex]\frac{2600-950}{2-5}[/tex]

   = -550

Therefore, equation of the line will be,

h = -550t + b

Since, point (2, 2600) lies on this line,

2600 = -550(2) + b

b = 2600 + 1100

b = 3700

So, equation of the line will be,

h = -550t + 3700

Input - output values for this line,

t            2             4            6  

h        2600      1500       400  

Now we can plot these points and get the graph of the line.

Answer:

di ko po alam ehh

Step-by-step explanation:

sorry po

Answer:

Step-by-step explanation:

What is the question?

Price reduced by $15

Percentage reduction = 15/60 = 0.25 = 25%

Answer:

4x+8=54 this is the correct answer