All categories

3 years ago

A store sells a note book for $3 each an does not charge

Mathematics

2 answers:

Andrej [43]3 years ago

8 0

I'm confused whats the question maybe i can help

Law Incorporation [45]3 years ago

6 0

So what your question

You might be interested in

Find a whole number between 9 4/9 and the square root of 144

postnew [5]

First, we'll want to write out the equation
$9 \frac{4}{9} < n < \sqrt{144}$

then reduce what we can
$9 \frac{4}{9} < n < 12$

so this means n can equal any whole number between 9 4/9 & 12, which gives us the options of {10,11}

$n = 10 \: or \: 11$

7 0

3 years ago

Consider the system of differential equations dxdt=−4ydydt=−4x. Convert this system to a second order differential equation in y

koban [17]

$\dfrac{\mathrm dy}{\mathrm dt}=-4x\implies x=-\dfrac14\dfrac{\mathrm dy}{\mathrm dt}\implies\dfrac{\mathrm dx}{\mathrm dt}=-\dfrac14\dfrac{\mathrm d^2y}{\mathrm dt^2}$

Substituting this into the other ODE gives

$-\dfrac14\dfrac{\mathrm d^2y}{\mathrm dt^2}=-4y\implies y''-16y=0$

Since $x(t)=-\dfrac14y'(t)$ , it follows that $x(0)=-\dfrac14y'(0)=4\implies y'(0)=-16$ . The ODE in $y$ has characteristic equation

$r^2-16=0$

with roots $r=\pm4$ , admitting the characteristic solution

$y_c=C_1e^{4t}+C_2e^{-4t}$

From the initial conditions we get

$y(0)=5\implies 5=C_1+C_2$

$y'(0)=16\implies-16=4C_1-4C_2$

$\implies C_1=\dfrac12,C_2=\dfrac92$

So we have

$\boxed{y(t)=\dfrac12e^{4t}+\dfrac92e^{-4t}}$

Take the derivative and multiply it by -1/4 to get the solution for $x(t)$ :

$-\dfrac14y'(t)=\boxed{x(t)=-\dfrac12e^{4t}+\dfrac92e^{-4t}}$

7 0

3 years ago

Urn 1 contains 3 blue tokens and 2 red tokens; urn 2 contains 2 blue tokens and 4 red tokens. All tokens are indistinguishable.

Dmitry_Shevchenko [17]

Answer:

RR = 0.4

RB = 0.3

BB = 0.22

BR = 0.30

Step-by-step explanation:

P( Urn 1 ) = 2/6 = 1/3

P( Urn 2 ) = 1 - 1/3 = 2/3

Urn 1 contains : 3 blue and 2 red

P( blue | urn 1 ) = 3/5 ( with replacement ) , P( blue | urn 1 ) = 3/4 ( without replacement )

P( red | urn 1 ) = 2 / 5 ( with replacement ) , P(red | urn 1 ) = 1/2 ( without replacement )

Urn 2 contains : 2 blue and 4 red

P ( blue | urn 2 ) = 1/3 ( with replacement ) , P( blue | urn 2 ) = 2/5 ( without replacement )

P ( red | urn 2 ) = 2/3 ( with replacement) , P( red | urn 2 ) = 4/5 ( without replacement )

Determine

<u>i) Possible outcomes when two tokens are drawn from either Urn without replacement </u>

RR = [[ ( 2/5 * 1/3 ) + ( 2/3 * 2/3 ) ] * [( 1/2 * 1/3 ) + ( 4/5 * 2/3 ) ]] = 0.4

RB = [[ (2/5 * 1/3 ) + ( 2/3 * 2/3 ) ] * [ ( 3/4 *1/3 ) + ( 2/5 * 2/3 ) ]] ≈ 0.3

BB = [[ ( 3/5 * 1/3 ) + ( 1/3 * 2/3 ) ] * [ ( 3/4 *1/3 ) + ( 2/5 * 2/3 ) ]] ≈ 0.22

BR = [[ ( 3/5 * 1/3 ) + ( 1/3 * 2/3 ) ] * [ ( 1/2 * 1/3 ) + ( 4/5 * 2/3 ) ]] ≈ 0.30

<u />

8 0

3 years ago

Three boxes of supplies have an average (arithmetic mean) weight of 7 kilograms and a median weight of 9 kilograms. What is the

GuDViN [60]

Answer:

Step-by-step explanation:

A) 1

(B) 2

(D) 4

(E) 5

Mean is a measure of central tendency. It is the average of a set of numbers. It is determined by adding the numbers together and dividing it by the total number

Mean = sum of numbers / number of observation

sum of numbers = 3 x 7 = 21

Median is the number that is at the center or middle of a set of obervations

x + 9+ y = 21

x= lowest number

y = highest number

x + y = 21 - 9

x + y = 12

If x = 1 y = 11

if x = 2 y = 10

if x = 3 y = 9

if x = 4 y = 8

the first 3 are plausible and the median would still be 9 if x = 4, median would be 8

3 0

2 years ago

Mrs. Connors went to the shopping mall and spent 3/5 of the money she had in her wallet at the department store. She bought new

Katen [24]

She spent 115 dollars on the pots and pans

7 0

3 years ago