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3 years ago

5

Solve the equation n/-3 =9

1 answer:

frez [133]3 years ago

7 0

Answer:

-27

Step-by-step explanation:

Multiply -3 times 9 to get -27. Check it by dividing -27 by -3. If you get 9 your correct.

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What kind of financial institutions does the Office of Thrift Supervision oversee?

xxTIMURxx [149]

Savings and Loan Institutions.

5 0

4 years ago

The Department of Agriculture is monitoring the spread of mice by placing 100 mice at the start of the project. The population,

uranmaximum [27]

Answer:

Step-by-step explanation:

Assuming that the differential equation is

$\frac{dP}{dt} = 0.04P\left(1-\frac{P}{500}\right)$ .

We need to solve it and obtain an expression for $P(t)$ in order to complete the exercise.

First of all, this is an example of the logistic equation, which has the general form

$\frac{dP}{dt} = kP\left(1-\frac{P}{K}\right)$ .

In order to make the calculation easier we are going to solve the general equation, and later substitute the values of the constants, notice that $k=0.04$ and $K=500$ and the initial condition $P(0)=100$ .

Notice that this equation is separable, then

$\frac{dP}{P(1-P/K)} = kdt$ .

Now, intagrating in both sides of the equation

$\int\frac{dP}{P(1-P/K)} = \int kdt = kt +C$ .

In order to calculate the integral in the left hand side we make a partial fraction decomposition:

$\frac{1}{P(1-P/K)} = \frac{1}{P} - \frac{1}{K-P}$ .

So,

$\int\frac{dP}{P(1-P/K)} = \ln|P| - \ln|K-P| = \ln\left| \frac{P}{K-P} \right| = -\ln\left| \frac{K-P}{P} \right|$ .

We have obtained that:

$-\ln\left| \frac{K-P}{P}\right| = kt +C$

which is equivalent to

$\ln\left| \frac{K-P}{P}\right|= -kt -C$

Taking exponentials in both hands:

$\left| \frac{K-P}{P}\right| = e^{-kt -C}$

Hence,

$\frac{K-P(t)}{P(t)} = Ae^{-kt}$ .

The next step is to substitute the given values in the statement of the problem:

$\frac{500-P(t)}{P(t)} = Ae^{-0.04t}$ .

We calculate the value of $A$ using the initial condition $P(0)=100$ , substituting $t=0$ :

$\frac{500-100}{100} = A}$ and $A=4$ .

So,

$\frac{500-P(t)}{P(t)} = 4e^{-0.04t}$ .

Finally, as we want the value of $t$ such that $P(t)=200$ , we substitute this last value into the above equation. Thus,

$\frac{500-200}{200} = 4e^{-0.04t}$ .

This is equivalent to $\frac{3}{8} = e^{-0.04t}$ . Taking logarithms we get $\ln\frac{3}{8} = -0.04t$ . Then,

$t = \frac{\ln\frac{3}{8}}{-0.04} \approx 24.520731325$ .

So, the population of rats will be 200 after 25 months.

6 0

3 years ago

Can some help me with this! Will Mark brainliest ❤️

Serhud [2]

If TU is 7.5 and UC is 17.5, TV = 25 because you just add the two together

3 0

3 years ago

What is the common ratio for geometric sequence: 5,15,45,135 ?

serg [7]

Answer:

the common ratio is 3

Step-by-step explanation:

to solve for the common ratio, I like to take the second term and divide it by the first term

15/5 = 3

then I will check the rest of the terms

15*3 = 45

45*3 = 135

It looks like the common ratio is correct!

5 0

3 years ago

2/5 = ?/15 plzzzzzzz help

timama [110]

5 x 3 = 15

2 x 3 = 6

So

2/5 = 6/15

Hope it helps

8 0

3 years ago

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