Find the density if it has a mass of 20g (mass per unit of volume)

Answer:

The expected mass of the sample in the year 2009 is approximately 60 miligrams.

Step-by-step explanation:

The mass of radioactive isotopes decays exponentially in time, the equation that represents this phenomenon is presented below:

[tex]m(t) = m_{o}\cdot e^{-\frac{t}{\tau} }[/tex] (1)

Where:

[tex]m(t)[/tex] - Current mass of the radioactive isotope, in miligrams.

[tex]m_{o}[/tex] - Initial mass of the radioactive isotope, in miligrams.

[tex]t[/tex] - Time, in years.

[tex]\tau[/tex] - Time constant, in years.

First, we must find the time constant associated to the decay of the radioactive isotope by clearing the respective term in (1):

[tex]-\frac{t}{\tau} = \ln \frac{m(t)}{m_{o}}[/tex]

[tex]\tau = -\frac{t}{\ln \frac{m(t)}{m_{o}} }[/tex]

If we know that [tex]t = 5\,y[/tex], [tex]m(t) = 190\,mg[/tex] and [tex]m_{o} = 800\,mg[/tex], then the time constant is:

[tex]\tau = -\frac{t}{\ln \frac{m(t)}{m_{o}} }[/tex]

[tex]\tau = -\frac{5\,y}{\ln \frac{190\,mg}{800\,mg} }[/tex]

[tex]\tau \approx 3.478\,y[/tex]

Now, we calculate the mass of the radioactive isotope in 2009 ([tex]t = 9\,y[/tex]). If we know that [tex]t = 9\,y[/tex], [tex]\tau \approx 3.478\,y[/tex] and [tex]m_{o} = 800\,mg[/tex], then the mass of the radioactive isotope is:

[tex]m(t) = m_{o}\cdot e^{-\frac{t}{\tau} }[/tex]

[tex]m(9\,y) = (800\,mg)\cdot e^{-\frac{9\,y}{3.478\,y} }[/tex]

[tex]m(9\,y) \approx 60.155\,mg[/tex]

The expected mass of the sample in the year 2009 is approximately 60 miligrams.

Answer: 7/8 of a mile

Answer:

58

Step-by-step explanation:

6*8+2*2+3*2=58

Answer:

[tex]1.2 \times 3.14[/tex]

Step-by-step explanation:

The ratio of a circumference to its diameter is equal to an irrational number, called pi, roughly equal to 3.14, denoted by symbol

[tex]\pi[/tex]

Therefore, knowing the diameter d, the circumference is equal to d*π

Answer:

0.83

9.96 divided by 12 is that

sorry I tried to find out the correct answer but because of one mistake I can't remember

Step-by-step explanation:

Given

[tex]q + p = 2(q - p)[/tex]

as equation 1.

I used q-p as the difference as logically the woman will be older than her son.

Also given,

[tex]qp = 675[/tex]

as equation 2.

Using equation 2,

[tex]q = \frac{675}{p} [/tex]

substitute this equation into equation 1.

[tex] \frac{675}{p} + p = 2( \frac{675}{p} - p) \\ \frac{675}{p} + p = \frac{1350}{p} - 2p \\ \frac{675}{p} - \frac{1350}{p} = - 2p - p \\ - 3p = - \frac{675}{p} \\ - 3p \times p = - 675 \\ - 3 {p}^{2} = - 675 \\ {p}^{2} = - 675 \div - 3 \\ {p}^{2} = 225 \\ p = \sqrt{225} \\ = 15[/tex]

Substitute P into equation 2.

[tex]15q = 675 \\ q = 675 \div 15 \\ = 45[/tex]

Therefore the woman is 45 years old while her son is 15 years old.

Answer:

h=4

Step-by-step explanation:

Subrtract 7, giving you 12.

Then divide by 3 to isolate h. Giving you 4.

Answer:

Step-by-step explanation:

25x-16y-25x+16y

-16y and 16y cancels out

25x-25x

25x and -25x cancels out too

This means the answer is 0

Answer:

Step-by-step explanation:

6 rectangles.

2 act as the top and bottom

Answer:

C and D

..............................

Step-by-step explanation:

correct

Answer:

Option C.

Step-by-step explanation:

Kay has the number 9.653

We want to find a number such that if we multiply this one by that number, the product will be larger than 9.6537​

First, you need to notice that 9.6537​ > 9.653

Now you need to remember that if we have a number A and a number B.

A*B > A if B > 1

A*B = A if B = 1

A*B < A if 0 < B < 1

Then we need to find an option with a number larger than 1.

Also, a rational number a/b is larger than 1 only if a > b

The only option which has an option larger than 1 is C.

C: 9/4 = 8/4 + 1/4 = 2 + 1/4

Answer:

B. Slope-intercept form is y = mx + b. M is slope, so it would be the one right in front of x which is -3 :)

Answer:

0.5

Step-by-step explanation:

6+ 4x = 8

or, 4x = 8-6

or, 4x = 2

x = 0.5

Answer:

Step-by-step explanation:

Draw the diameter from point (-1, -5) to point (2, 3).

The triangle has base 3 and height 8.

The diameter of the semicircle is the hypotenuse of the triangle.

The radius is half the diameter.

The total area is the area of the triangle plus the area of the semicircle.

Answer:

A) 10.5+7.25[tex]\pi[/tex]units²

Step-by-step explanation:

This can be divided into a semicircle and a right triangle.

The area of the right triangle is (1/2)(7)(3)= 10.5

the radius of the semicircle is

[tex]d=\sqrt{7^{2} +3^{2} } )=\sqrt{(49+9)} =\sqrt{58}[/tex]

[tex]r=(1/2)(\sqrt{58}[/tex]

[tex]A=(1/2\pi (1/2)(\sqrt{58)^{2} }[/tex]

[tex]A=58\pi /8[/tex]

[tex]A=7.25\pi[/tex]

[tex]---------[/tex]

hope it helps..

have a great day!!

Answer:

well if you think about it the answer you see is in the points

Step-by-step explanation:

and the data comes from the scatterplot so try to see it and remember to chose b or c ok  

Step-by-step explanation:

Hi,

I agree with what you did. You could also add y on both sides and get 3x = y + 5 and then divided by three to get...

x = 5 + y /3

(the 5 and y are being divided by 3)

But that's just complicated, it works, but it's complicated. What you did is correct and what I gave you is the value of x, but I'm 100 percent sure yours is correct.

Hope this helps

Answer and Step-by-step explanation:

Yes (technically),  there is a different way to answer the equation 3x - y = 5. But, the first part of how you described it is a bit off.

Here is how you would explain it:

What you would do is Add y to both sides, then subtract 5 from both sides.

3x = y + 5

3x - 5 = y (aka y  = 3x - 5)

The other way to solve:

3x - y = 5

Subtract 3x from both sides.

-y = -3x + 5

Now divide both sides by -1.

-1(-y) = -1(-3x + 5)

y = 3x - 5

If you want to solve for x, you would:

Add y to both sides of the equation.

3x = 5 + y

Then divide each side by 3.

x = [tex]\frac{1}{3}y[/tex] + [tex]\frac{5}{3}[/tex]

#teamtrees #PAW (Plant And Water)

Answer:

Formula for percent change is C = {x_2 - x_1}/{x_1}  

C = relative change

x_1 = initial value

x_2 = final value

Step-by-step explanation:

Answer:

<_> daddy

Step-by-step explanation:

Answer:

i would say true

Step-by-step explanation:

Answer:

i think its D

Step-by-step explanation:

Answer:

A

Step-by-step explanation:

Answer:

243 ft³

Step-by-step explanation:

V = [tex]\frac{1}{3}[/tex]Bh

A = 9 x 9 = 81

81 x 9 = 729

729 / 3 = 243

When you see [tex]\frac{1}{3}[/tex] in a math formula, it means to divide by 3.

For example, when you are trying to find the volume of a pyramid or cone you will see [tex]\frac{1}{3}[/tex] in the formula.

Let me know if this helps!

Answer:

729 ft³

Step-by-step explanation:

I found this answer by something I learned. All you have to do is multiply the 3 numbers of the square pyramid.

9 x 9 x 9 = 729 ft³

Answer:

b

Step-by-step explanation:

Answer:

The answer is B

Step-by-step explanation:

Area of small rectange = 7 cm × 4 cm = 28 cm sq

Area of bigger rectangle = 4cm×10 cm = 40 cm sq

Area of traingle = 1/2 × 8*3 cm sq = 12 cm sq

total area of polygon = ( 28 + 40 + 12 ) cm sq

area of polygon = 80 cm sq

Answer:

All the points in the scatter plot are written as (x, y)

Where x is the value in the horizontal axis (in this case the weight)

and y is the value in the vertical axis (in this case, the number of seeds)

We want to know the weight of 100 seeds.

We know that the number of seeds is represented in the vertical axis.

Then, first let's look at the vertical axis and find the value 100.

Now let's move horizontally the right until we meet the point.

Once we meet the point, let's move vertically to the horizontal axis, and see in which value we intersect the axis.

If we do that, we can see that we will intersect the x-axis at the value x = 5.

And this axis represents the weight in kg, then the weight of 100 seeds is 5kg.

Answer:

88

Step-by-step explanation:

MATH

The number of students who have the flu on Friday morning will be;

⇒ 83

What is mean by Percentage?

A number or ratio that can be expressed as a fraction of 100 or a relative value indicating hundredth part of any quantity is called percentage.

Given that;

The number of students at a particular school who have the flu is increasing at a rate of 12% per day.

At the beginning of Monday there were 56 students with the flu,

Now,

Since, The number of students at a particular school who have the flu is increasing at a rate of 12% per day.

Hence, The percent of increasing rate on Friday morning = 4 x 12%

                                                                                         = 48%

Thus, The number of students who have the flu on Friday morning is,

⇒ 56 + 48% of 56

⇒ 56 + 48 × 56 / 100

⇒ 56 + 26.88

⇒ 82.88

Thus, The number of students who have the flu on Friday morning will be;

⇒ 83

Learn more about the percent visit:

https://brainly.com/question/24877689

#SPJ2

Answer:

2

Step-by-step explanation:

So the common ratio is simply what a number can be multiplyied by. To find this, all we have to do is see how many times one number goes into the one after it.

So lets take the 20(2nd number), lets divide it by 10(1st number). What do we get when we divide the numbers? We get 2. since 10 goes into 20, 2 times.

Lets see if the common ratio 2 checks out for the other numbers. What is 80(4th number) divided by 40(3rd number)? Well again, thats 2. Since 40 goes into 80, 2 times.

So, we can conclude that the answer is 2.

Answer:

I think the common ratio is 20

Step-by-step explanation:

Each number is 20 times the previous number, so the Common Ratio would have to be 10

Answer:

(0.69, 0.91)

Step-by-step explanation:

Hope this helps!

The 99% confidence interval for p is (0.698, 0.902), which is closest to option (B) (0.70, 0.90).

A confidence interval is a range of values that are constrained by the statistic's mean and that are likely to include an unidentified population parameter. The proportion of likelihood, or certainty, that the confidence interval would include the real population parameter when a random sample is drawn several times is referred to as the confidence level.

To find the 99% confidence interval for the proportion of adults who shop online, we need to use the formula:

CI = p ± z√((p(1-p))/n)

where p is the sample proportion (72/90 = 0.8), n is the sample size (90), and z is the z-score corresponding to the 99% confidence level (from the z-table, this is 2.576).

Substituting the values, we get:

CI = 0.8 ± 2.576√((0.8(1-0.8))/90)

Simplifying, we get:

CI = 0.8 ± 0.102

Therefore, the 99% confidence interval for p is (0.698, 0.902).

To learn more about the confidence interval;

https://brainly.com/question/24131141

#SPJ7

Answer:

you are missing part of the question

Step-by-step explanation: