1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ahat [919]
3 years ago
9

Suppose that news spreads through a city of fixed size of 700000 people at a time rate proportional to the number of people who

have not heard the news. (a.) Formulate a differential equation and initial condition for y(t), the number of people who have heard the news t days after it has happened. No one has heard the news at first, so y(0)=0. The "time rate of increase in the number of people who have heard the news is proportional to the number of people who have not heard the news" translates into the differential equation
Mathematics
1 answer:
Gnoma [55]3 years ago
8 0

Answer:

y'(t) = k(700,000-y(t))  k>0 is the constant of proportionality

y(0) =0

Step-by-step explanation:

(a.) Formulate a differential equation and initial condition for y(t) = the number of people who have heard the news t days after it has happened.

If we suppose that news spreads through a city of fixed size of 700,000 people at a time rate proportional to the number of people who have not heard the news that means  

<em>dy/dt = k(700,000-y(t)) </em>where k is some constant of proportionality.

Since no one has heard the news at first, we have

<em>y(0) = 0 (initial condition) </em>

We can then state the initial value problem as

y'(t) = k(700,000-y(t))

y(0) =0

You might be interested in
How to solve (8x-30)+(6x+10)=180
lozanna [386]
Add the like terms. So I'll add the variables. 8x+6x is 14x. Now add whole numbers. 30+10 is 40. Our new expression we'll be 14x+40=180. Subtract 40 from 180. 180-40=140. Now we have the expression 14x=140. 140 divided by 14 is 10. So x is 10.
7 0
3 years ago
Find the value of n in this equation.
lisabon 2012 [21]

Answer:

  • D. 9

=========================

<h2>Given </h2>

Triangle with:

  • Base of n² -3,
  • Midsegment of 39.

<h2>To find</h2>

  • The value of n.

<h2>Solution</h2>

As per definition of midsegment, it is connecting the midpoints of two sides and its length is half the length of the opposite side of the triangle.

So we have:

  • (n² - 3)/2 = 39

Solve it for n:

  • n² - 3 = 78
  • n² = 81
  • n = √81
  • n = 9

Correct choice is D.

3 0
1 year ago
a pizza shop offers 30% off the price of a large pizza every Tuesday night. If the regular price is $25, what is the discounted
Elina [12.6K]
You need do like 25$--------100% of real price
                         x$---------70%


25x70=100<u>x</u>
1,750=100<u>x</u>
    <u> x</u>=1750<u />divided by 100=17.5$
5 0
3 years ago
Read 2 more answers
-2=3(y-2) how do you solve this problem for y​
Ksivusya [100]

Answer:

y= 4/3

Step-by-step explanation:

Step 1: Simplify both sides of the equation.

−2=3(y−2)

−2=(3)(y)+(3)(−2)(Distribute)

−2=3y+−6

−2=3y−6

Step 2: Flip the equation.

3y−6=−2

Step 3: Add 6 to both sides.

3y−6+6=−2+6

3y=4

Step 4: Divide both sides by 3.

3y /3 = 4 /3

y= 4/3

Answer:

y= 4/3

8 0
3 years ago
Here a brainliest if you get it right
oksian1 [2.3K]

Answer:

D.(2, 2)

Step-by-step explanation:

  • Staring point = (2, -4)
  • Since he moved 6 units up, so, there will be change in only y-coordinate of the starting point and x-coordinate will remain unchanged.
  • End point of the segment = (2, - 4 + 6) = (2, 2)
3 0
2 years ago
Other questions:
  • Find the surface area of a sphere with a diameter of 32 mm. Express your answer in terms of π.
    7·2 answers
  • What is 79.623 rounded to the nearest hundred??
    11·1 answer
  • Mrs. Varner deposited q dollars in a bank account that has been earning annual interest. The total value of the account is based
    6·2 answers
  • What is the area of the inside surface of the ball to the nearest cm^2 ?
    8·1 answer
  • What is the mean length of gestation for the data set? Round to the nearest tenth.
    10·1 answer
  • A manager samples the receipts of every fifth person who goes through the line. Out of 50 people, 4 had a mispriced item. If 600
    6·1 answer
  • If y=2 2/3 when x=1/4, find y when x=1 1/8
    6·1 answer
  • PLEASE HELPPP<br><br>put in order from greatest to least -1 3/8. -0.4, -1.55. -9/16​
    5·1 answer
  • A number is increased by 25% and the resulting number is then decreased by 20%. The final number is what percent of the original
    12·1 answer
  • Geraldo and Raul are participating in a relay for charity. Geraldo rides his bike 12​ miles per hour. Raul rides his bike 10​ mi
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!