Beryllium-li decomposes into boron-li with a half-life of
13.8 seconds. How long will it take 2400 g of beryllium-il
to decompose into 75 g of beryllium-il? (3 marks)

Answers

Answer 1

[tex]\textit{Amount for Exponential Decay using Half-Life} \\\\ A=P\left( \frac{1}{2} \right)^{\frac{t}{h}}\qquad \begin{cases} A=\textit{current amount}\dotfill &75\\ P=\textit{initial amount}\dotfill &2400\\ t=seconds\\ h=\textit{half-life}\dotfill &13.8 \end{cases} \\\\\\ 75=2400\left( \frac{1}{2} \right)^{\frac{t}{13.8}}\implies \cfrac{75}{2400}=\left( \frac{1}{2} \right)^{\frac{t}{13.8}}\implies \cfrac{1}{32}=\left( \frac{1}{2} \right)^{\frac{1}{13.8} t}[/tex]

[tex]\log\left( \cfrac{1}{32} \right)=\log\left[ \left( \frac{1}{2} \right)^{\frac{1}{13.8} t} \right]\implies \log\left( \cfrac{1}{32} \right)=t\log\left[ \left( \frac{1}{2} \right)^{\frac{1}{13.8}} \right] \\\\\\ \cfrac{\log\left( \frac{1}{32} \right)}{\log\left[ \left( \frac{1}{2} \right)^{\frac{1}{13.8}} \right]}=t\implies \cfrac{\log\left( \frac{1}{32} \right)}{\log\left[ \sqrt[13.8]{\frac{1}{2}} \ \right]}=t\implies 69\approx t[/tex]


Related Questions

Calculate the percent

Answers

Answer:

95% of 28 is 26.6

Step-by-step explanation:

28 * 0.95 = 26.6

Answer:

•SEE ABOVE ATTACHMENT•

HOPE IT HELPS!

MARK AS BRAINLIAST.

1. Oscar and Eli set up a lemonade stand. If they have prepared 2 1/2 gallons of lemonade, how many 1-cup servings can they sell? A) 10 B 20 C
40 D 80​

Answers

Answer:

40 cups

Step-by-step explanation:

There are 16 cups in one gallon. So 16 * 2 1/2 = 40

When fully charged, Jaylin's
computer works for 20 hours.
She uses her computer for about
1.5 hours each day. A low battery
warning comes on when there is
hours of use or less remaining

Answers

Answer:

The battery seems to be charging at a rate of 1 percentage point per minute. So the battery should be fully charged at 10:11 AM.

Step-by-step explanation:

Find N in this equation: N X 4 divided by 2 + 5 - 1 = 20

Answers

Hi!

4n/2+5-1=202n+4=202n=20-42n=16n=8

What value of x makes the equation true? 6 6x + 8 = 3x - 19 : A. X=-9 B. -- 3 C. = -3 D. x= 3​

Answers

Answer:

A. x = -9

Step-by-step explanation:

6x + 8 = 3x - 19 <== subtract 3x from both sides

-3x       -3x

3x + 8 = -19 <== subtract 8 from both sides

    - 8     - 8

3x = -27 <== divide both sides by 3

/3     /3

x = -9

Hope this helps!

Answer:

[tex]\tt x=-9[/tex]

Step-by-step explanation:

[tex]\tt 6x + 8 = 3x - 19[/tex]

Subtract 8 from both sides:-

[tex]\tt 6x+8-8=3x-19-8[/tex]

[tex]\tt 6x=3x-27[/tex]

Subtract 3x from both sides:-

[tex]\tt 6x-3x=3x-27-3x[/tex]

[tex]\tt 3x=-27[/tex]

Divide both sides by 3:-

[tex]\tt \cfrac{3x}{3}=\cfrac{-27}{3}[/tex]

[tex]\tt x=-9[/tex]

The vaule of x that makes the equation true is A) x= -9.

A quality analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that whenever this process is in control, package weight is normally distributed with a mean of 20 ounces and a standard deviation of two ounces. Each day last week, he randomly selected four packages and weighed each: Day Weight (ounces) Monday 23 22 23 24 Tuesday 23 21 19 21 Wednesday 20 19 20 21 Thursday 18 19 20 19 Friday 18 20 22 20 What is the sample mean package weight for Thursday

Answers

Using it's concept, it is found that the sample mean package weight for Thursday is of 19 ounces.

What is the mean of a data-set?

The mean of a data-set is given by the sum of the observations divided by the number of observations.

For Thursday, the package weights in ounces are given by: {18, 19, 20, 19}.

Hence, the sample mean in ounces is of:

M = (18 + 19 + 20 + 19)/4 = 19.

More can be learned about the mean concept at https://brainly.com/question/24628525

Sushil was thinking of a number. Sushil halves the number and gets an answer of 61.4. Form
an equation with x from the information.
X

Answers

61.4⋅2=x
x=122.8

hope this helps!

Solve 96 =3w+ 15, where w is a real number.
2
Round your answer to the nearest hundredth?

Answers

Answer:

3+15=18 i guess

Step-by-step explanation:

dont judge me im only in 2 grade

The volume of the sphere is 500 - cubic units.
3
What is the value of x?
04 units
O 5 units
----
O 8 units
O 10 units

Answers

Answer:

8 po yan po sagot ko .. correct me if I wrong

How do do this problem

Answers

Answer:

42 in

Step-by-step explanation:

The lengths of the tangent segments drawn from an external point to a circle are equal.

AT and RT meet at point T

⇒ AT = RT = 9 in

RE and GE meet at point E

⇒ RE = GE = 5 in

AN and NG meet at point N

⇒ AN = GN = 7 in

Total perimeter = AT + RT + RE + GE + GN + AN

                          = 9 + 9 + 5 + 5 + 7 + 7

                          = 42 in

Please help asap !!!!

Answers

C

Step-by-step explanation:

You do 5 - 2 = 3 and -y = -x so the answer would be C.

(-5, -5) (1,3) find the distance between each pair of points

Answers

Answer:

10

Step-by-step explanation:

Plug into Distance formula --> √(1 - (-5))^2 + (3 - (-5))^2

---> 10

What is the value of (-4)-3?
1
64
О.

1
12
64
ОО
1
12

Answers

Answer:

Answer is -1/64

Step-by-step explanation:

Mark me the brilliant

The length of a rectangle is six times its width.
If the perimeter of the rectangle is 126 in, find its area. Answer in inch ^2

Answers

Answer:

486 square inches.

Step-by-step explanation:

126 = w + 6w + w + 6w

126 = 14w

width = 9 inches

A = wl

A = (9)(9*6)

A = 486 square inches

Find the product or expression:
(a+16)2​

Answers

Answer:

[tex]\boxed{\sf{2a+32}}[/tex]

Step-by-step explanation:

You have to use a distributive property.

Distributive property:

→ A(B+C)=AB+AC

⇒ (a+16)2

→ 2(a+16)

Multiply.

⇒ 2*a=2a

→ 2*16=32

Rewrite the problem down.

⇒ 2a+32

Therefore, the correct answer is 2a+32.

I hope this helps you! Let me know if my answer is wrong or not.

Hi!

Given:

[tex](a+16)2[/tex]

See the 2 out in front of the parentheses? Using the distributive property, we need to multiply that 2 by each of the terms inside of the parentheses. See the attached image below for more information.

So:

[tex]2*a+16*2[/tex]

[tex]2a+32[/tex]

Therefore, your answer is 2a + 32

1 point
2. Three boards are unloaded into the factory.
А
B
С
Board A is three times the length of board C, plus 5 inches. Board B is two
times the length of board C, plus 3 inches. The total length of all three boards
is 104 inches. How long is each board?
Your answer
??

Answers

Each side of the board would have to be at least 36

Find the area of the triangle with the following coordinates. A (-5,9) B (1,-7) C (8,4)

Answers

QUESTION : > FIND THE ARE OF THE TRIANGLE WITH THE FOLLOWING COORDINATES.

A. (-5,9)

B . (1,-7)

C . (8,4)

ANSWER :> A.

(-5,9).

HOPE IT HELPS

THANK ME LATER.

#CARY ON LEARNING

What number must you add to complete the square?

x^2 - 16x = 23

A. -8

B. -64

C. 64

D. 8

Answers

Answer:

D

Step-by-step explanation:

Answer:

D. 8

Step-by-step explanation:

To create a trinomial square on the left side of the equation, find a value that is equal to the square of half of b.

(b/2) ² = (-8)²

Add the term to each side of the equation.

x² - 16x + (-8)² = 23 + (-8)²

Simplify the equation.

Raise -8 to the power of 2.

x² - 16x + 64 = 23 + (-8)²

Simplify 23 - (-8)²

Raise - 8 to the power of 2.

x² - 16x + 64 = 23 + 64

Add 23 and 64

x² - 16x + 64 = 87

Factor the perfect trinomial square into (x-8)²

(x-8)²=87

Solve the equation for x.

Take the square root of each side of the equation to set up the solution for x.

(x-8)²*¹/₂ = ±√87

Remove the perfect root factor x-8 under the radical to solve for x.

x - 8 = ±√87

Remove parentheses.

x - 8 = ±√87

Add 8 to both sides of the equation.

x = ±√87 + 8

The result can be shown in multiple forms.

Exact Form:

x = ±√87 + 8

Decimal Form:

x=17.32737905…,−1.32737905…

What is the solution to 2x + 5 = 6x – 5? Show your work.

Answers

Answer:

2x - 6x = -5-5

-4x = -10

4x = 10

x = 10/4

Therefore, x= 5/2.

Solve:
x + 1/x = 4 1/4


Ans: 4,1/4​

Answers

Answer:

x = 4, 1/4

solving steps

[tex]\sf \rightarrow x + \dfrac{1}{x}=4\dfrac{1}{4}[/tex]

make the denominators same

[tex]\sf \rightarrow \dfrac{x(x)}{x} + \dfrac{1}{x}=4\dfrac{1}{4}[/tex]

simplify the following

[tex]\sf \rightarrow \dfrac{x^2}{x} + \dfrac{1}{x}=\dfrac{17}{4}[/tex]

join both fractions together

[tex]\sf \rightarrow \dfrac{x^2+1}{x}=\dfrac{17}{4}[/tex]

cross multiply

[tex]\sf \rightarrow 4(x^2+1)=17(x)[/tex]

simplify

[tex]\sf \rightarrow 4x^2-17(x)+4=0[/tex]

completing square

[tex]\sf \rightarrow 4x^2-16(x)-x+4=0[/tex]

factor

[tex]\sf \rightarrow 4x(x-4)-1(x-4)=0[/tex]

group the variables

[tex]\sf \rightarrow (4x-1)(x-4)=0[/tex]

simplify

[tex]\sf \rightarrow (x-4)=0, \ (4x-1) =0[/tex]

final answer

[tex]\sf \rightarrow x=4, \ x =\dfrac{1}{4}[/tex]

Answer:

[tex]\boxed{x = \dfrac{1}{4}}[/tex] and [tex]\boxed{x = 4}[/tex]

Step-by-step explanation:

Given equation:

[tex]x + \dfrac{1}{x} = 4\dfrac{1}{4}[/tex]

Step-1: Convert the mixed fraction on the R.H.S into improper fraction

[tex]x + \dfrac{1}{x} = 4\dfrac{1}{4}[/tex]

[tex]x + \dfrac{1}{x} = \dfrac{4 \times4 + 1}{4}[/tex]

[tex]x + \dfrac{1}{x} = \dfrac{16 + 1}{4}[/tex]

[tex]x + \dfrac{1}{x} = \dfrac{17}{4}[/tex]

Step-2: Make common denominators on the L.H.S:

[tex]x + \dfrac{1}{x} = \dfrac{17}{4}[/tex]

[tex]\dfrac{x^{2} }{x} + \dfrac{1}{x} = \dfrac{17}{4}[/tex]

Step-3: Combine the denominators on the L.H.S

[tex]\dfrac{x^{2} }{x} + \dfrac{1}{x} = \dfrac{17}{4}[/tex]

[tex]\dfrac{x^{2} +1}{x} = \dfrac{17}{4}[/tex]

Step-4: Use cross multiplication

[tex]\dfrac{x^{2} +1}{x} = \dfrac{17}{4}[/tex]

[tex]x^{2} +1} = \dfrac{17x}{4}[/tex]

[tex]4(x^{2} +1}) = {17x}[/tex]

Step-5: Simplify the distributive property

[tex]4(x^{2} +1}) = {17x}[/tex]

[tex]4x^{2} +4} = {17x}[/tex]

[tex]-17x + 4x^{2} +4} = 0[/tex]

Step-6: Change "-17x" to "-16x - x" as it is equivalent

[tex]-17x + 4x^{2} +4} = 0[/tex]

[tex](-16x - x) + 4x^{2} +4} = 0[/tex]

Step-7: Factor the common terms

[tex](-16x - x) + 4x^{2} +4} = 0[/tex]

[tex]-16x - x + 4x^{2} +4} = 0[/tex]

[tex]4x(-4 + x) - 1(x - 4) = 0[/tex]

Step-8: Group the terms

[tex]4x(-4 + x) - 1(x - 4) = 0[/tex]

[tex](x - 4)(4x - 1) = 0[/tex]

Step-9i: Use cross multiplication for (x - 4)

[tex](x - 4)(4x - 1) = 0[/tex]

[tex]x - 4 = \dfrac{0}{4x - 1 } = 0[/tex]

Step-9ii: Use cross multiplication for (4x - 1)

[tex](x - 4)(4x - 1) = 0[/tex]

[tex]4x - 1 = \dfrac{0}{x - 4} = 0[/tex]

Thus [tex]x - 4 = 0[/tex] and [tex]4x - 1 = 0[/tex].

Step-10: Simplify both equations

[tex]4x - 1 = 0[/tex]                  [tex]x - 4 = 0[/tex]

[tex]4x = 0 + 1[/tex]                  [tex]x = 0 + 4[/tex]

[tex]4x = 1[/tex]                          [tex]\boxed{x = 4}[/tex]

[tex]\boxed{x = \dfrac{1}{4}}[/tex]

Age of car = 4 years. Original cost = $13,850. The current market value is $

Answers

Using an exponential function, supposing that the value decays 10% a year, it is found that the current market value is $9,087.

What is an exponential function?

A decaying exponential function is modeled by:

[tex]A(t) = A(0)(1 - r)^t[/tex]

In which:

A(0) is the initial value.r is the decay rate, as a decimal.

In this problem, supposing a decay of 10% a year, and the original value of $13,850, the parameters are A(0) = 13850, r = 0.1.

Hence, the value of the car in 4 years is given by:

[tex]A(t) = A(0)(1 - r)^t[/tex]

[tex]A(4) = 13850(0.9)^4[/tex]

A(4) =  9087.

More can be learned about exponential functions at https://brainly.com/question/25537936

When do I use the quadratic formula?

Answers

Answer:

Step-by-step explanation:

Quadratic equations are commonly used in situations where two things are multiplied together and they both depend on the same variable. For example, when working with area, if both dimensions are written in terms of the same variable, you use a quadratic equation.

What is the area of this triangle ?

Answers

Answer:

8

Step-by-step explanation:

area of a triangle= b x h x 1/2 or b x h /2

the base is 4 and the height is 4

4x4/2

=16/2

=8

What is sin 45°?
O
45°
VE
1
90°
45°
1
O
O A. /
O B. v
O C. 1
O D.
1
2

Answers

Answer:

A

Step-by-step explanation:

A

The value of sin 45° is,

⇒ sin 45° = 1/√2

We have to given that,

A triangle is shown in image.

We know that,

sin x = Opposite / Hypotenuse

Now, By given triangle,

sin 45° = 1/√2

Therefore, The value of sin 45° is,

⇒ sin 45° = 1/√2

Learn more about the triangle visit;

brainly.com/question/1058720

#SPJ7

Two forces of 560 N and 222 N act at a point. The resultant force is 634 N. Find the angle between the forces.

Answers

The angle between the two forces of 560 N and 222 N is 80.96°

What is the resultant of two vectors?

The resultant of two vectors P and Q refer to the magnitudes of the vectors and it can be expressed by the formula [tex]\mathbf{R = \sqrt{P^2 +Q^2 +2PQ cos \theta }}[/tex]

Now, using the above equation, we can easily determine the angle between the forces of the two vectors as follows:

[tex]\mathbf{634 = \sqrt{560^2 +222^2 + 2(560 \times 222) \ Cos \theta }}[/tex]

[tex]\mathbf{401956 =313600 +49284 + 248640 \ Cos \theta }}[/tex]

[tex]\mathbf{401956 -313600 -49284 = 248640 \ Cos \theta }}[/tex]

[tex]\mathbf{39072= 248640 \ Cos \theta }}[/tex]

[tex]\mathbf{ Cos \theta = \dfrac{39072}{248640}}}[/tex]

[tex]\mathbf{Cos \theta =0.1571}[/tex]

[tex]\mathbf{ \theta =80.96^0}[/tex]

Therefore, we can conclude that the angle between the forces is 80.96°

Learn more about the resultant of two vectors here:

https://brainly.com/question/19802988

helpppp: Find the area of the parallelogram.

Answers

Step-by-step explanation:

that is totally simple.

the area of a parallelogram is

baseline × height

basically the same as for a rectangle, just that in this more general form the height is no longer the other side.

in our case here

18×13 = 234 cm²

A boy bought 1,567kg of frozen chicken,657g of vegetables and 95g of corn oil from a shopping mall. What is the total weight of the items she bought in kilograms​

Answers

Answer:

1567.752

Step-by-step explanation:

1000g = 1 kg. Before you can add them together, you have to multiply the vegetables and corn oil by 0.001 so that they are now in the unit of Kilograms. Then just add all of them together

Answer:

1567.752

Step-by-step explanation:

On January 1, 2022 Hideki Matsuyama provides services in exchange for a $10,000 zero-interest bearing note due in 4 years. The effective interest rate for a note of this type is 15 percent. How much revenue does Hideki recognize on January 1, 2022?

Answers

Hideki recognizes a $17,490.06 revenue.

Revenue

Given that on January 1, 2022 Hideki Matsuyama provides services in exchange for a $10,000 zero-interest bearing note due in 4 years, and the effective interest rate for a note of this type is 15 percent, to determine how much revenue does Hideki recognize on January 1, 2022 the following calculation must be made:

10000 x 1.15^4 = X10000 x 1.749 = x17490.06 = X

Therefore, Hideki recognizes a $17,490.06 revenue.

Learn more about revenue in https://brainly.com/question/14695611

Answer:

Hideki recognizes a $17,490.06 revenue.

Step-by-step explanation:

how is 12 x √3/2 = 6√3 ?

Answers

[tex]12x\sqrt{\cfrac{3}{2}}~~ = ~~6\sqrt{3}\implies (6)(2)x\cdot \cfrac{\sqrt{3}}{\sqrt{2}}~~ = ~~6\sqrt{3}\implies \cfrac{(2x)(6\sqrt{3})}{\sqrt{2}}=6\sqrt{3} \\\\\\ \cfrac{2x}{\sqrt{2}}=\cfrac{6\sqrt{3}}{6\sqrt{3}}\implies \cfrac{2x}{\sqrt{2}}=1\implies 2x=\sqrt{2}\implies x=\cfrac{\sqrt{2}}{2}[/tex]

A researcher is studying the growth of bacteria. He starts with 260 of the bacteria. It grows continuously at a rate of 1% per hour. How many bacteria will there be in 6 hours?​

Answers

[tex]\bold{ANSWER:}[/tex]
276.0775

[tex]\bold{EXPLANATIONS:}[/tex]
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