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2 years ago

7

i am greater than 1/4 but less than 4/10. i am a decimal rounded to the hundredths place with the digit 1 in my hundredths place

. what number am i?

2 answers:

lions [1.4K]2 years ago

7 0

The answer is 0.3. because it's between 0.25 and 0.4 rounded

kati45 [8]2 years ago

5 0

The number is 0.31.

3 is in the tenths place
1 is in the hundredths place

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1 quart is equal to 4 cups given this fact what is 8 quarts equivalent to in cups

SVETLANKA909090 [29]

8 quarts is equal to 32 cups :)

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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.

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3 years ago

1. c+z when c = 3 and z = 17

ivann1987 [24]

1) 3+17= 20
2) 40-15= 25
3) 3 x 20= 60
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3 years ago

A rectangle's perimeter is equal to 27 plus its width. The length of the rectangle is four times its width. What is the

lara31 [8.8K]

Answer:

P = 3

Step-by-step explanation:

L = 4*w

P = 27 + w

P = 2*L + 2*w = 27 + w

2L = 2*(4w) = 8w

Put that into the perimeter formula (the first one.)

P = 8w + 2w = 27 + w

10w = 27 + w Subtract w from both sides

9w = 27 Divide by 9

w = 27 / 9

w = 3

You should find the Length just so you can check it.

L = 4w

L = 4*3

L = 12

Check

P = 2L + 2w

P = 2*12 + 2*3 = 30

P = 27 + w

P = 27 + 3

P = 30 and everything checks.

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eight out of 10 dentist prefer Crest toothpaste.What is the ratio of dentist whi prefer Crest to those who do

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The ratio would be 8:2

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