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3 years ago

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A card is drawn from a stands 52 card deck what is the probability that the card is a red card, or that it is a ten of clubs or

a jack of clubs A. 1/52 B. 3/26 C. 7/13 D. 15/26

1 answer:

marusya05 [52]3 years ago

5 0

Answer:

d. 15/26

Step-by-step explanation:

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Find the area of the complex figure.

Rzqust [24]

To find the area of this figure, there is two choices
1. cut it into 3 rectangles.
2.find the missing rectangle in the middle......
I likes 2 better $_$ :}

find the missing area in the middle, 12* 23 = 276
the area of the whole figure 31*69-276=1863m²

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3 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

Answer this and your a legend

ivanzaharov [21]

Answer:

1 = 1 liter

2 = 1 kiloleter

3 = 1 quart

4 = 1 pint

5 = 1 cup

6 = 1 gallon

Step-by-step explanation:

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3 years ago

What is four hundred twenty-eight and forty-six hundredths written in standard form? 5th grade

Akimi4 [234]

Answer:

4.2846*10^2

Step-by-step explanation:

428.46

4.2846*10^2 hopefully

6 0

3 years ago

There are three numbers. The first number is twice the second number. The third number is twice the first number. The sum of the

mel-nik [20]

Answer:

x = 32 y = 16 z = 64

Step-by-step explanation:

x is the 1st number

y is the 2nd number

z is the 3rd number

The first number is twice the second number so

x = 2 y

The third number is twice the first number.

z = 2 x

Their sum is 112

x + y + z = 112

Plus in what we know:

x + y + z = 112

2 y + y + 2x = 112

3y + 2x = 112 Let's solve for y and subtract 2x from each side

3y = 112 - 2x Divide both sides by 3

y = $\frac{112 - 2x}{3}$

Now plug our answer back in to solve for x.

x = 2y

x = 2 ( $\frac{112 - 2x}{3}$ )

x = (224 - 4x) / 3 Multiply each side by 3.

3x = 224 - 4x Add 4x to each side

3x + 4x = 224

7x = 224 Divide each side by 7

7x / 7 = 224 / 7

x = 32

Now we can solve for z.

z = 2x

z = 2 ( 32 )

z = 64

Now we can solve for the numerical value of y.

x + y + z = 112

32 + y + 64 = 112

96 + y = 112 Subtract 96 from each side.

y = 112 - 96

y = 16

5 0

3 years ago

Read 2 more answers