The half-life of Radium-226 is 1590 years. If a sample contains 200 mg, how many mg will remain after 1000 years?

Answers

Answer 1

Answer: 129.33 g

Step-by-step explanation:

[tex]$$Let $p=A \cdot e^{n t}$ \\$(p=$ present amount, $A=$ initial amount, $n=$ decay rate, $t=$ time)[/tex]

[tex]\begin{aligned}&\Rightarrow \text { Given } p=\frac{A}{2} \ a t \ t=1590 \\&\Rightarrow \frac{1}{2}=e^{1590n} \Rightarrow n=\frac{\ln (1 / 2)}{1590}=-0.00043594162\end{aligned}[/tex]

[tex]$$If $A=200 \mathrm{mg}$ and $t=1000$ then,$$\begin{aligned}P &=200 e^{\left(\frac{\ln \left(1/2\right)}{1590}\right) \cdot 1000} \text \\\\&=129.33 \text { grams}\end{aligned}$$[/tex]


Related Questions

100 POINTS
Solve x4 - 10x² + 9 = 0.

Answers

Answer:

[tex]x=\pm1 \:\textsf{or}\:x=\pm3[/tex]

Step-by-step explanation:

[tex]x^4-10x^2+9=0[/tex]

[tex]\textsf{let}\:x^2=y[/tex]

[tex]\implies y^2-10y+9=0[/tex]

To factor a quadratic in the form [tex]ax^2+bx+c[/tex], find 2 two numbers that multiply to [tex]ac[/tex] and sum to [tex]b[/tex].

⇒ two numbers that multiply to 9 and sum to -10:  -9 and -1

Rewrite [tex]b[/tex] as the sum of these 2 numbers:

[tex]\implies y^2-y-9y+9=0[/tex]

Factorize the first two terms and the last two terms separately:

[tex]\implies y(y-1)-9(y-1)=0[/tex]

Factor out the common term [tex](y-1)[/tex]:

[tex]\implies (y-9)(y-1)=0[/tex]

[tex]\implies (y-9)=0 \implies y=9[/tex]

[tex]\implies (y-1)=0 \implies y=1[/tex]

Change [tex]y[/tex] back to [tex]x^2[/tex]:

[tex]\implies x^2=9\implies x=\pm3[/tex]

[tex]\implies x^2=1\implies x=\pm 1[/tex]

[tex]\textsf{So}\: x=\pm1 \:\textsf{or}\:x=\pm3[/tex]

Answer:

[tex]$x=\pm1\;\textrm{or}\;x=\pm3$[/tex]

Step-by-step explanation:

Substitute [tex]u = x^2[/tex] into the equation. This will make the quadratic formula easy to use.

[tex]\implies u^2 - 10u + 9 = 0[/tex]

Consider the form [tex]x^2 + bx + c = 0[/tex]. Find a pair of integers whose product is [tex]c[/tex] and whose sum is [tex]c[/tex]. In this case, whose product is [tex]9[/tex]and whose sum is [tex]10[/tex]. And write the factored form using the integers.

[tex]\implies (u - 9)(u - 1) = 0[/tex]

If any individual factor on the left side of the equation is equal to [tex]0[/tex], the entire expression will be equal to [tex]0[/tex].

[tex]\implies \begin{cases}u - 9 = 0 \\ \\ u - 1 = 0\end{cases}[/tex]

Set [tex]u - 9[/tex] equal to [tex]0[/tex] and solve for [tex]u[/tex]. Similarly, Set [tex]u - 1[/tex] equal to [tex]0[/tex] and solve for [tex]u[/tex].

[tex]\implies \begin{cases}u = 9 \\ \\ u = 1\end{cases}[/tex]

Substitute the real value of [tex]u = x^2[/tex] back into the solved equation.

[tex]\implies \begin{cases}x^2 = 9 \\ \\ x^2 = 1\end{cases}[/tex]

Take the square root of both sides of the equations to eliminate the exponent on the left side.

[tex]\implies \begin{cases}x = \sqrt{9} \\ \\ x = \sqrt{1}\end{cases}[/tex]

Solve both the equations for the value of [tex]x[/tex].

[tex]\implies \begin{cases}x = \pm3 \\ \\ x = \pm1\end{cases}[/tex]

Hence, this is our required solution for this question.

[tex]\rule{300}{1}[/tex]

Additional information:

There are three ways to solve a quadratic equation:

FactoringComplete the SquareQuadratic Formula

Factoring uses the logic that the product of any number and zero is zero. Complete the square method uses square root, and the quadratic formula is the simpler method of it.

Quadratic Formula [tex]x=\dfrac{-b\pm\sqrt{b^2-4ac} }{2a}[/tex]

13.
Hamza made 6 calls in
one day. Each call cost the
same amount of
money. The next day he made a
call that cost $4. Which expression
represents the total cost of the calls Hamza made during the two
days?

Answers

Answer:

6x +4 where x is amount for standard call

Step-by-step explanation:

Answer:

4c+6

Step-by-step explanation:

Right on my test

using appropriate property find -2/5 ×1/5 + 2/5 × 1/5


Answers

Answer:

simply cut 5 and solve if no property needed but if needed use distributive

Find the minimum value of X²+6X-5​

Answers

Answer:

x = -3, y = -14

Step-by-step explanation:

Graph it

X=-3, Y= -14
Graph it

Find two positive numbers whose difference is 27 and whose product is 874.​

Answers

46 and 19. 46 x 19 = 874 and 46 - 19 = 27

same homework. different question.

Answers

Answer:

Answer = B. Obtuse.

Step-by-step explanation:

Maggie takes three electives: art, Spanish, and creative writing. She calculated the mean absolute deviation of the points she earned throughout the year in each class. art: mean absolute deviation of 2.1
Spanish: mean absolute deviation of 0.8
creative writing: mean absolute deviation of 2.7
In which elective were her scores the most spread out?

Answers

Answer:

0.8 seconds sorry if im wrong

Step-by-step explanation:

Find the equation of the tangent to the curve y = 4x³- 5x² + x - 3 at the point where it crosses the y axis.​

Answers

Answer:

y = x-3

Step-by-step explanation:

When the graph of this equation crosses the y - axis , the value of x is = 0.

 sub in zero to find this y value = -3

    so the point is (0, -3)

Now find the drivative of this equation....the derivative tells you the slope of the original graph at any given point

 derivative = 12x^2-10x+1        this , when x = 0 shows slope  = 1

    the equation then becomes   y = (1) x -3     or just  y = x-3

 See image below

Answer:

-3

Step-by-step explanation:

put x= 0

help me please…………..

Answers

hope this helps
answer: b
explained below
The answer is B!

Since both terms are perfect squares, factor using the difference of squares formula

Ryan invested $257 in an account paying an interest rate of 3.9% compounded weekly.
What is the equation?

Answers

Answer:

The equation is 257/x = x/3.9

Step-by-step explanation:

Bilquis owns a small business selling used books. She knows that in the last week 49 customers paid cash, 42 customers used a debit card, and 32 customers used a credit card.
Based on these results, express the probability that the next customer will pay with a credit card as a decimal to the nearest hundredth.

Answers

The probability that the next customer will pay with a credit card will be  0.26 or 26%.

What is probability?

Probability means possibility. It deals with the occurrence of a random event. The value of probability can only be from 0 to 1. Its basic meaning is something is likely to happen. It is the ratio of the favorable event to the total number of events.

Bilquis owns a small business selling used books. She knows that in the last week 49 customers paid cash, 42 customers used a debit card, and 32 customers used a credit card.

Then the probability that the next customer will pay with a credit card will be

[tex]\rm P = \dfrac{32}{123}\\\\ P = 0.26[/tex]

More about the probability link is given below.

https://brainly.com/question/795909

#SPJ1

Answer:

The answer is .26

Step-by-step explanation:

32/123

0.260162...

richard has two circular sprinklers to water his rectangular backyard as shown.

Answers

Answer:

109.88 ft² (nearest hundredth)

Step-by-step explanation:

Formulae

Area of a rectangle = width × lengthArea of a circle = πr²

To find the area of the lawn that is not watered, subtract the area of the 2 circles from the area of the rectangle.

From inspection of the diagram

width of rectangle = 2rlength of rectangle = 4rarea = 512 ft²

Substituting the values into the area of a rectangle formula, and solving for r:

⇒ 512 = 2r × 4r

⇒ 512 = 8r²

⇒ r² = 64

⇒ r = ±8

As distance is positive, r = 8 ft

Area of one circle = π8² = 64π  ft²

Therefore,

Area not watered = area of rectangle - 2 × area of circle

                             = 512 - 2(64π)

                             = 109.88 ft² (nearest hundredth)

3)
A mobile phone company uses the formula C = 10t + 20m to calculate the total cost
of a bill.
C is the total cost of the bill in pence
t is the number of text messages
m is the number of minutes of call time
Calculate the total cost for 150 texts and 50 minutes of call time.
р

Answers

Answer:

2500 pence (C = 2500)

Step-by-step explanation:

[tex]C = 10t + 20m[/tex]

From the given information, t is the number of texts so essentially you will plug in the number of texts provided (150) in the place of the variable t.

[tex]C = 10(150) + 20m[/tex]

Apply the same thing to minutes, plug in the number of minutes (50) in the place of the variable m.

[tex]C = 10(150) + 20(50)[/tex]

Now multiply the substitutes with the co-efficient.

[tex]C = 1500 + 1000[/tex] (10*150=1500 & 20*50=1000)

Add the addends

C = 2500

4. The number of feet in a yard can be represented by a graph. Circle the graph(s) that could
be used to represent the number of feet, y, in x yards.
GRAPH A
GRAPH B
GRAPH
GRAPHD
27
26
21
18
LS
60
54
48
42
36
30
20
18
12
135
12
105
9
75
6
60
54
40
42
36
30
24
18
12
9
45
3
3
15
6

Answers

i need to see the graphs is it possible to add a photo ??

A factory makes aquariums. Each aquarium is in the shape of a triangular prism, as shown below. If the factory makes 288 aquariums, how much water will be needed to fill all of them (in cubic feet)?

Answers

Answer:

384

Step-by-step explanation:

solve:
-0.4k-6=1.2

If you answer this you're a God

Answers

Answer:

The answer is k = -18

Step-by-step explanation:

This is so easy... so first you do -2k/5 - 6 = 1.2

                                                     -2k + 5(-6)/5 = 1.2

                                                      and then all that divided by 5

A sum of money was distributed among some boys. Had there been two boys more, each would have received Rs. 10 less. Had there been two boys less, each would have received Rs. 15 more. Find the number of boys and the sum received by each.​

Answers

Given -

A sum of money was distributed among some boys.Had there been two boys more, each would have received Rs. 10 less.Had there been two boys less, each would have received Rs. 15 more.

To find -

the number of boys and the sum received by each.

Explanation -

Here as we are required to find the value of two different individuals hence first we will from 2 linear equations into two variables (taking each to be value as x and y or whatever you like, I will take them as a and b) will solve the equation by any method of your choice (explanation for them is in the link, below, it is given by the same me)

https://brainly.com/question/27161912?utm_source=android&utm_medium=share&utm_campaign=question

Solution -

Let the sum of money that was given to each boy be a and the number of boys be b. Hence, the total no. of money distributed to b no. of boys is ab.

According to the question,

Scenario 1 -

➡ (a + 2)(b - 10) = ab

Solving it further,

➡ a(b - 10) + 2(b - 10)= ab

➡ ab - 10a + 2b - 20= ab

Cancelling ab,

10a - 2b + 20 = 0

10a = 2b - 20

➡ a = 2(b - 10)/10

a = (b - 10)/5

Scenario 2 -

➡ (a - 2)(b + 15) = ab

Solving it further,

➡ a(b + 15) - 2(b + 15)= ab

➡ ab + 15a - 2b - 30= ab

Cancelling ab,

15a - 2b - 30 = 0

Substituting the value of a in the equation,

➡ 15{(b - 10)/5} - 2b - 30 = 0

➡ 3(b - 10) - 2b - 30 = 0

➡ 3b - 30 - 2b - 30 = 0

➡ 3b - 2b -60 = 0

b = 60

Substituting the value of b in a = (b - 10)/5,

➡ a = (60 - 10)/5

➡ a = 50/5

a = 10

[Here we have used the substitution method]

Henceforth, the total number of boys is 60 and the sum received by each is Rs. 10 .

5* 3 1/3 I have to have my math done in an hour and I don’t know this

Answers

16.65... .... ..... ...

Answer: 16.65

Step-by-step explanation:

1/3 is equivalent to the decimal value .33

so, use the equation:

5x(3+.33) or 5x3.33, which equals 16.65

what's the estimate of 6.48 + 9.34

Answers

Answer:

6+9=15

Step-by-step explanation:

hope this helps :D

The point A(5.
7) is reflected over the
What are the coordinates of point B?
point (6,
6) and its
image is point B.

Answers

The point (6, 6) is the mid-point of A and B. Then the coordinate of the point B is (7, 5).

What is coordinate geometry?

Coordinate geometry is the study of geometry using the points in space. Using this, it is possible to find the distance between the points, the dividing line is m:n ratio, finding the mid-point of the line, etc.

Point A (5, 7) is reflected over the point (6, 6) and its image is point B. Then the point (6, 6) is the mid-point of the A and B. Then the coordinate of the point B will be

[tex]\rm (x_2 , y_2) = (2x -x _1, 2y - y_1)\\\\(x_2 , y_2) = (2 \times 6 - 5, 2 \times 6- 7)\\\\(x_2 , y_2) = (12-5,12-7)\\\\(x_2 , y_2) = (7, 5)[/tex]

More about the coordinate geometry link is given below.

https://brainly.com/question/1601567

#SPJ1

Which of the following options have the same value as 10 % , percent of 33?

Answers

Answer:

3.3

Step-by-step explanation:

33 x .10 = 3.3

Hey can somebody help me on this?

Answers

Answer: 7

Step-by-step explanation: g = 8 ( given ) g/2+3 plugging the value of g 8/2+3

8+3x2

   2

  8+6

    2

   14

    7

   = 2

Pablo's father is 4 years older than his mother and Pablo is a third his mother's age.
If their combined age is 74 years

Answers

Answer: 11

Explanation:

Find an equation of the line passing through the pair of points (3,5) and (6,11). Write the equation in the form Ax+By=C

Answers

Answer: (4,8)

Step-by-step explanation:

Ye Li drew another quadrilateral it is a parallelogram and has four right angles can it be rhombus?

Answers

Answer:

A rhombus is both a rectangle and a rhombus. All the sides are equal and each angle measure 90 degrees. So yes it can be a rhombus.

Step-by-step explanation:

Answer:

No.

Step-by-step explanation:

A squares angles are all 90 degree, a rhombus however, has perpendicular angles crossing each other that are equal to 90 degress.

Please help. I need the answer

Answers

Answer:

B

Step-by-step explanation:

[tex]m-5\neq 5-m[/tex]

The others follow the rules of the commutative property of multiplication/addition.

Answer:

B

m - 5

Step-by-step explanation:

1) division

2) m - 5 . Since subtraction is not commutative

{4x+y=9 and 5x +2y=9
use substitution method to find all solutions of the system of equations

(X,y)=

Answers

Answer:

x=3,y=-3

Step-by-step explanation:

Isolate x for 4x +y=9: x=9-y/4

Substitute x = 9-y/4

[5 x 9-y/4+2y =9]

Isolate y for (45+3y/4)=9:

y=-3

For x= 9-y/4

Substitute y = -3

x= 9-(-3)/4

9-(-3)/4=3

X=3

The solutions to the system of equations are:

x=3 y= -3

pls help i need an A my mom is going to get mad at me pls help i will give 62 points

Answers

Answer:

I would say the second one

Step-by-step explanation: Good luck! :)

which number has a 9 with a value ten times greater than the 9 in 4 903

Answers

Answer:

49030

Step-by-step explanation:

we multiply it by ten so

4903×10=49030

Hi can someone please help me

Answers

Answer:

Last and second lastv

Step-by-step explanation:

According to the rational factorization.

Other Questions
just need help with solving for x 100 POINTS WILL MARK BRAINLIEST NEED BY 9:00Solve the linear equation below. Show ALL your work AND explain the type of solution you found! 8 - 2(4v + 6) = - 4 - 8v Is a triangle with the side lengths 4 feet, 7. 5 feet, and 8. 5 feet a right triangle? Why or why not? What are some of the ways the print revolution transformed Europe? can you find the slope -intercept equation of each line code ? Plan an investigation to explore the evidence that an electric current produces a magnetic field, and that a changing magnetic field produces an electric current. How did Hitler use the Munich Pact to expand German territory? (This isn't history this is Science but on brainly it doesn't show the subject) Please help me with this y'all The model shows global atmospheric circulation. Identify the wind directions that are correct. Arctic Circle Tropic of Cancer Equator Tropic of Capricorn Antarctic Circle Fidelity bonds insureO A. employersO B. marine vesselsO C. automobile driversO D. employees What did Redi find in his experiment?- Both broths contained living organisms.- Only the broth with the flask open to the air contained living organisms.- Flies were found in all of the sealed and unsealed jars of rotting meat.- Flies were not found in the sealed jars of rotting meat. Jason is traveling to a dry desert. he knows that cactuses hold water and was told that desert animals do not eat the cactuses for food or water. what is the best explanation of why the cactuses are not eaten by animals? the stem makes a cactus too tall for predators to eat. the spines protect the cactus from predators eating it. animals do not eat plants for food or water. a cactus stores its water in its roots far away from predators. Judges 21:25 In those days there was no king in Israel; everyone did what was right in his own eyes. According to this verse, if the children of Israel had a king, they would do what was right in God's sight. TrueFalse What is this suffering ? ( Think back to the gospels ( see Luke 22:47-23:49)) Suppose a town has a population of 5,000 residents but that the population is decreasing by 200 people each year. Write a linear function to represent the population of the town in terms of the numbers of years. After how many years will the town have a population of 1,800? When will the town have only 400 residents? Math 50 points Please Help Which best summarizes the effects of mutations on organisms?Mutations are sometimes helpful, sometimes harmful, and sometimes neutral.Mutations are usually harmful, sometimes neutral, and never helpful.Mutations are sometimes neutral, sometimes helpful, and never harmful.Mutations are always harmful, never helpful, and never neutral.I NEED THE ANSWER PLS HELP!!!!!!!! formular for area of a circle please help me find the same denominator The parabola in the image has its focus at (4,3).Its directrix is the line y=1.The point (8,6) is on the parabola.