Answer:
Decay rate K = -2.44%
Step-by-step explanation:
From the question, we want to know the decay rate of strontium 90
Mathematically, this is accessible from its decay equation
From the decay equation, we can see that that ;
At = Ao e^-0.0244t
Generally, the decay equation of a radioactive sample can be written as
At = Ao e^-kt
where K represents the decay constant
From the equation, we can see that;
k = 0.0244 which when represented as a percentage is 2.44%
Since it’s a decay we can say that the decay rate is -2.44%
The answer is : -2.44%
Solve the following system of equations. Express your answer as an ordered pair in the format (a,b). 3x+4y=17 -4x-7y=-18
Answer:
Step-by-step explanation:
3x+4y = 17 _______ equation 1
-4x -7y= -18 _______ equation 2
muliply by 4 in equation 1
12x + 16y = 68 ______ equation 3
multiply by 3 in equation 2
-12x - 21y = -54 ________ equation 4
add equation 3 & 4
- 5y = 14
y = - 14/5
substitute y in equation 1
3x + 4 (-14/5) =17
3x = 17+ (56/5)
3x =( 85 + 56) / 5
3x = 141/5
x = 47/5
hence (a,b) = (47/5, -14/5)
Exhibit 2-4A survey of 400 college seniors resulted in the following crosstabulation regarding their undergraduate major and whether or not they plan to go to graduate school. Undergraduate Major Graduate SchoolBusinessEngineeringOtherTotal Yes 35 42 63140 No 91104 65260 Total126146128400Among the students who plan to go to graduate school, what percentage indicated "Other" majors
Answer:
The percentage of college seniors with "Other" majors is 32%.
Step-by-step explanation:
The total number of college seniors surveyed is, N = 400.
The number of college seniors with "Other" majors is, n = 128.
The percentage of a value of x from N total is given as follows:
[tex]\text{Percentage of}\ x=\frac{x}{N}\times 100\%[/tex]
Compute the percentage of college seniors with "Other" majors as follows:
[tex]\text{Others}\%=\frac{n}{N}\times 100\%[/tex]
[tex]=\frac{128}{400}\times 100\%\\\\=32\%[/tex]
Thus, the percentage of college seniors with "Other" majors is 32%.
Solve triangle ABC given:
(a) angle A = 40°, angle B = 60°, b = 8 cm.
(b) a = 4, b = 5, c = 6.
(c) angle B = 104°, a = 17 cm, c = 11 cm.
Answer:
(a) C = 80 a = 5.938cm c = 9.097cm
(b) unsure
(c) b= 22.147cm
A = 48.16 degrees
C = 22.82 degrees
Note angle sum higher than 180 due to rounding inaccuracies
Step-by-step explanation:
(a) <C == 180 - (40 + 60) == 80 (Interior angles on triangle have sum of 180 degrees)
side a = (8*sin(40))/sin(60) == 5.938cm by law of sines
side c = (8*sin(80))/sin(
60) == 9.097cm by law of sines
(b) unsure
(c) b^2 = 17^2 + 11^2 - 2(17)(11)cos(104) --> Law of cosines
b^2 = 289 + 121 - 2(187)cos(104)
b^2 = 400 - -90.479
b^2 = 490.479
b = 22.147 cm
sin(A)/17cm = sin(104)/22.147cm
A = arcsin((17/22.147)*sin(104))
A = 48.16 degrees
sin(C)/11cm = sin(104)/22.147cm
C = arcsin((11/22.147)*sin(104))
C = 28.82 degrees
Drag the labels to the correct locations
Answer:
Graph A
So it has two distinct real roots.
Graph B
It has one repeated real root
Graph C
So it has two complex roots.
Graph D
One real root and one complex root
Step-by-step explanation:
For graph A
The value of the roots is x= 1 and x= 3
And the minimum value = -3
It's a positive graph
So it has two distinct real roots.
For graph B
The value of the roots is x = 2 and x= 2
That is x= 2 twice
Has a maximum value of 0
It's an inverse graph
It has one repeated real root
For graph C
It's a positive graph but on the negative of x
Has a minimum value of 1
It didn't touch x at y = 0
And it's root will be negative
So it has two complex roots.
For Graph D
Value of the roots is x= 2 and x= -2
It's a positive graph
Minimum value of -4
One real root and one complex root
Two passenger trains traveling in opposite directions meet and pass each other. Each train is 1 12 mi long and is traveling 50 mph. How many seconds after the front cars of the trains meet will their rear cars pass each other?
Answer:
Time taken = 6 sec (Approx)
Step-by-step explanation:
Given:
Total distance = 1/12 mi = 0.083333
Speed of train = 50 mph = 50 / 3600 = 0.01388889 mps
Find:
Time taken
Computation:
Time taken = Total distance / Speed
Time taken = Total distance / Speed of train
Time taken = 0.0833333 / 0.01388889
Time taken = 6 sec (Approx)
Set up a rational equation and then solve the following problems. A positive integer is twice another. The sum of the reciprocals of the two positive integers is 3/14. Find the two integers.
Answer:
7 and 14
Step-by-step explanation:
let one integer = x
other integer = 2x
sum of reciprocal = 1/x + 1/2x
= 3/2x = 3/14
= x = 7
one no. = 7
other no. = 14
How do you write in decimals eight and three tenths
Answer:
8.3
Step-by-step explanation:
What is the approximate volume of the cone? Use 3.14 for π. radius-16 height-9
Answer:
2411.52
Step-by-step explanation:
1/3(3.14*16*16*9) = 2411.52
Answer:
2411.52 units³Step-by-step explanation:
Given,
Radius ( r ) = 16
Height ( h ) = 9
pi ( π ) = 3.14
Volume of cone = ?
Now, let's find the volume of cone:
[tex]\pi \: {r}^{2} \frac{h}{3} [/tex]
plug the values
[tex]3.14 \times {16}^{2} \times \frac{9}{3} [/tex]
Evaluate the power
[tex]3.14 \times 256 \times \frac{9}{3} [/tex]
Calculate the product
[tex]2411.52 \: {units}^{2} [/tex]
Hope this helps..
Best regards!!
What point lies on the line described by the equation below? Y+3=2 (x-1
Answer:
[tex]\boxed{(1, -3)}[/tex]
Step-by-step explanation:
[tex]y+3=2 (x-1)[/tex]
Put equation in slope-intercept form.
[tex]y=mx+b[/tex]
[tex]y=2(x-1)-3[/tex]
[tex]y=2x-2-3[/tex]
[tex]y=2x-5[/tex]
Let x = 1
[tex]y=2(1)-5[/tex]
[tex]y=2-5[/tex]
[tex]y=-3[/tex]
The point (1, -3) lies on the line.
Use the Ratio Test to determine the convergence or divergence of the series. If the Ratio Test is inconclusive, determine the convergence or divergence of the series using other methods.
[infinity] n = 1 n2/5n n = 1
lim n→[infinity] an + 1/an =
a. converges
b. diverges
Answer:
A. The series CONVERGESStep-by-step explanation:
If [tex]\sum a_n[/tex] is a series, for the series to converge/diverge according to ratio test, the following conditions must be met.
[tex]\lim_{n \to \infty} |\frac{a_n_+_1}{a_n}| = \rho[/tex]
If [tex]\rho[/tex] < 1, the series converges absolutely
If [tex]\rho > 1[/tex], the series diverges
If [tex]\rho = 1[/tex], the test fails.
Given the series [tex]\sum\left\ {\infty} \atop {1} \right \frac{n^2}{5^n}[/tex]
To test for convergence or divergence using ratio test, we will use the condition above.
[tex]a_n = \frac{n^2}{5^n} \\a_n_+_1 = \frac{(n+1)^2}{5^{n+1}}[/tex]
[tex]\frac{a_n_+_1}{a_n} = \frac{{\frac{(n+1)^2}{5^{n+1}}}}{\frac{n^2}{5^n} }\\\\ \frac{a_n_+_1}{a_n} = {{\frac{(n+1)^2}{5^{n+1}} * \frac{5^n}{n^2}\[/tex]
[tex]\frac{a_n_+_1}{a_n} = {{\frac{(n^2+2n+1)}{5^n*5^1}} * \frac{5^n}{n^2}\\[/tex]
aₙ₊₁/aₙ =
[tex]\lim_{n \to \infty} |\frac{ n^2+2n+1}{5n^2}| \\\\Dividing\ through\ by \ n^2\\\\\lim_{n \to \infty} |\frac{ n^2/n^2+2n/n^2+1/n^2}{5n^2/n^2}|\\\\\lim_{n \to \infty} |\frac{1+2/n+1/n^2}{5}|\\\\[/tex]
note that any constant dividing infinity is equal to zero
[tex]|\frac{1+2/\infty+1/\infty^2}{5}|\\\\[/tex]
[tex]\frac{1+0+0}{5}\\ = 1/5[/tex]
[tex]\rho = 1/5[/tex]
Since The limit of the sequence given is less than 1, hence the series converges.
* *4.8.21
Question Help
After the release of radioactive material into the atmosphere from a nuclear power plant in a country in 1982, the hay in that country was contaminated by a radioactive
isotope (half-life 5 days). If it is safe to feed the hay to cows when 9% of the radioactive isotope remains, how long did the farmers need to wait to use this hay?
The farmers needed to wait approximately
(Round to one decimal place as needed.)
days for it to be safe to feed the hay to the cows.
Vo
1.
(1,1)
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Enter your answer in the answer box and then click Check Answer.
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8
a
Answer:
17.5 days
Step-by-step explanation:
The half life of this element is five days.
For the first five days it will decrease to 100*0.5=50%.
For the second five days it will decrease to 50*0.5= 25%
For the third five days it will decrease to 25*0.5 = 12.25%
It means in each day in the five days it reduce 0.1 of the it's remaining amount.
12.5 - 9 = 3.5 %
0.5 of 12.5 = 6.25%
It's going to be 15 days + 2.5 days= 17.5 days
A firm has 18 senior and 22 junior partners. A committee of three partners is selected at random to represent the firm at a conference. In how many ways can at least one of the junior partners be chosen to be on the committee?
Answer:
Answer is 24288.
Step-by-step explanation:
Given that there are 18 senior and 22 junior partners.
To find:
Number of ways of selecting at least one junior partner to form a committee of 3 partners.
Solution:
At least junior 1 member means 3 case:
1. Exactly 1 junior member
2. Exactly 2 junior member
3. Exactly 3 junior member
Let us find number of ways for each case and then add them.
Case 1:
Exactly 1 junior member:
Number of ways to select 1 junior member out of 22: 22
Number of ways to select 2 senior members out of 18: 18 [tex]\times[/tex] 17
Total number of ways to select exactly 1 junior member in 3 member committee: 22 [tex]\times[/tex] 18 [tex]\times[/tex] 17 = 6732
Case 2:
Exactly 2 junior member:
Number of ways to select 2 junior members out of 22: 22 [tex]\times[/tex] 21
Number of ways to select 1 senior member out of 18: 18
Total number of ways to select exactly 2 junior members in 3 member committee: 22 [tex]\times[/tex] 21 [tex]\times[/tex] 18 = 8316
Case 3:
Exactly 3 junior member:
Number of ways to select 3 junior members out of 22: 22 [tex]\times[/tex] 21 [tex]\times[/tex] 20 = 9240
So, Total number of ways = 24288
The half-life of iron-52 is approximately 8.3 hours. Step 1 of 3: Determine a so that A(t)=A0at describes the amount of iron-52 left after t hours, where A0 is the amount at time t=0. Round to six decimal places.
Answer:
Step-by-step explanation:
Given the half like of a material to be 8.3 hours and the amount of iron-52 left after t hours is modeled by the equation [tex]A(t) = A_0 a^{t}[/tex], we can get A(t) as shown;
At t = 8.3 hours, A(8.3) = 1/2
Initially at t = 0; A(0) = 1
Substituting this values into the function we will have;
[tex]\frac{1}{2} = 1 * a^{8.3}\\\\Taking \ the \ log \ of\ both \ sides;\\\\log(\frac{1}{2} ) = log(a^{8.3} )\\\\log(\frac{1}{2} ) = 8.3 log(a)\\\\\fr-0.30103 = 8.3 log(a)\\\Dividing\ both\ sides\ by \ 8.3\\\\\frac{-0.30103}{8.3} = log(a)\\\\log(a) = - 0.03627\\\\a =10^{-0.03627} \\\\a = 0.919878 (to\ 6dp)[/tex]
A baseball is hit into the air, and its height h in feet after t seconds is given by h(t)= -16t^2+128t+2. The height of the baseball when it is hit is ? The baseball reaches its maximum height after ? The maximum height of the baseball is ?
Answer:
[tex]\large \boxed{\sf \ \text{2 feet, 4 seconds, 258 feet } \ }[/tex]
Step-by-step explanation:
Hello,
To know the height of the baseball when it is hit we have to compute h(0), as t = 0 is when the baseball is hit into the air.
[tex]h(0)=-16\cdot 0^2+128 \cdot 0+2=2[/tex]
So, the answer is 2 feet.
h(x) is a parabola which can be written as [tex]ax^2+bx+c[/tex], it means that the vertex is the point (-b/2a,h(-b/2a)).
The baseball reached its maximum height after
[tex]\dfrac{-b}{2a}=\dfrac{-128}{-2*16}=\boxed{4 \text{ seconds}}[/tex]
And the maximum height of the baseball is h(4).
[tex]h(0)=-16\cdot 4^2+128 \cdot 4+2=-256+512+2=\boxed{258 \ \text{feet}}[/tex]
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
Actividad 1.1<br />Investigue sobre el tema de diferenciabilidad en un punto para encontrar los valores de "a" y "b" tales que<br />la función<br />definida a continuación sea diferenciable en t = 2, luego construya su gráfica.<br />at +b, sit < 2<br />f(t) = {2t2 – 1, si 2 st<br />1
Answer:
a = 8
b = -8
Step-by-step explanation:
You have the following function:
[tex]f(x)\\\\=at+b;\ \ t<2\\\\2t^2-1;\ \ 2\leq t[/tex]
A function is differentiable at a point c, if the derivative of the function in such a point exists. That is, f'(c) exists.
In this case, you need that the function is differentiable for t=2, then, you have:
[tex]f'(t)=a;\ \ \ \ t<2 \\\\f'(t)=4t;\ \ \ 2\leq t[/tex]
If the derivative exists for t=2, it is necessary that the previous derivatives are equal:
[tex]f'(2)=a=4(2)\\\\a=8[/tex]
Furthermore it is necessary that for t=2, both parts of the function are equal:
[tex]8(2)+b=2(2)^2-1\\\\16+b=8-1\\\\b=-8[/tex]
Then, a = 8, b = -8
Solve the system by substitution. x−5y=13 4x−3y=1 Enter your answer as an ordered pair (x,y).
Answer:
(-2,-3)
Step-by-step explanation:
Well in the system,
x−5y=13
4x−3y=1
We need to find x or y in either equation.
Let's do x - 5y = 13 for x.
+5y to both sides
x = 5y + 13
Now we substitute 5y + 13 for y in 4x - 3y = 1.
4(5y + 13) - 3y = 1
20y + 52 - 3y = 1
17y + 52 = 1
-52 to both sides
17y = -51
Divide all by 17
y = -3
Now we can substitute -3 for y in 4x - 3y = 1.
4x - 3(-3) = 1
4x + 9 = 1
-9 to both sides
4x = -8
Divide 4 to both sides
x = -2
Thus,
the solution is (-2,-3).
Hope this helps :)
Answer:
( - 2 , - 3 )Step-by-step explanation:
x - 5y = 13
4x - 3y = 1
Solve the equation for x
[tex]x - 5y = 13[/tex]
Move '5y' to R.H.S and change it's sign
[tex]x = 13 + 5y[/tex]
Substitute the given value of X into the equation
4x - 3y = 1
[tex]4(13 + 5y) - 3y = 1[/tex]
Solve the equation for y
distribute 4 through the parentheses
[tex]52 + 20y - 3y = 1[/tex]
Collect like terms
[tex]52 + 17y = 1[/tex]
Move constant to R.H.S and change it's sign
[tex]17y = 1 - 52[/tex]
Calculate
[tex]17y = - 51[/tex]
Divide both sides of the equation by 17
[tex] \frac{17y}{17} = \frac{ - 51}{17} [/tex]
Calculate
[tex]y = - 3[/tex]
Now, substitute the given value of y into the equation
x = 13 + 5y
[tex]x = 13 + 5 \times ( - 3)[/tex]
Solve the equation for x
Multiply the numbers
[tex] = 13 - 15[/tex]
Calculate the difference
[tex] = - 2[/tex]
The possible solution of the system is the ordered pair
( x , y )
( x , y ) = ( - 2 , - 3 )
-----------------------------------------------------------------------
Check if the given ordered pair is the solution of the system of equation
[tex] - 2 - 5 \times ( - 3) = 15[/tex]
[tex]4 \times ( - 2) - 3 \times ( - 3) = 1[/tex]
Simplify the equalities
[tex]13 = 13[/tex]
[tex]1 = 1[/tex]
Since all of the equalities are true, the ordered pair is the solution of the system
( x , y ) = ( - 2 , - 3 )Hope this helps..
Best regards!!
FIRST ANSWER GETS BRAINLIEST!!!
How do you write 0.00696 in scientific notation?
Answer:
6.96x10^-3
Step-by-step explanation:
0.00696
We move the decimal point to between 6 and 9
since the number with the decimal point should be between 0 and 9.
Then we count the numbers.
6.96x10^-3.
Hope this helps. ❤❤❤
Answer: 6.96 * 10^(-3)
Step-by-step explanation:
In scientific notation, you multiply a number that has a value in the ones place and no value in the tens place by 10 raised to an exponent.
Hope it helps <3
match the inequality, x²≥0, with it's equivalent interval notation
Answer:
[tex](-\infty, \infty)[/tex]
Step-by-step explanation:
Every number, when you raised to the second power is positive, therefore that inequality would be all real numbers.
[tex](-\infty, \infty)[/tex]
On a recent shopping trip, you see a sale advertising 3 pairs of socks and 2 pairs of shoes for $60. Write an equation using x to represent the cost of socks and y to represent the cost of shoes.
Answer:
3x + 2y =60
Step-by-step explanation:
x = socks
y = shoes
3x + 2y =60
Answer:
3x + 2y =60
Step-by-step explanation:
Hope this Helps you !
Write the equation of the line, in point-slope form. Identify (x, y) as the point (-2, 2). Use the box provided or the upload
option to submit all of your calculations and final answers.
Answer:
y = -x + 0
Step-by-step explanation:
well the equation of a line is y = mx + b
m = the slope , b = the y-intercept
m = y2 - y1 / x2 - x1
m = -1
and b is the y-intercept of the line.
finally:
y = -1x + 0
Which is the equation of the line for the points in the given table
Answer:
A...............................
Find the valuds to complete the table
Answer:
Where is the table
Step-by-step explanation:
I cant answer without it
If I set my alarm to read 8:10 when it is really 8:00 (i.e., it is 10 minutes fast) and the alarm goes off each day when it reads 8:10, it will be ___________ but not ___________.
Answer:
If I set my alarm to read 8:10 when it is really 8:00 (i.e., it is 10 minutes fast) and the alarm goes off each day when it reads 8:10, it will be reliable but not valid.
Step-by-step explanation:
If I set my alarm to wake me earlier than I need to be woken, it might be in order to give me enough time to adjust to the alarm, and be awake enough to get out of bed before the normal time I need to be out of bed. This method is very reliable, as there is a very little probability of me waking up late, since I have a 10 minutes head start everyday to get out of bed. The problem is that this method is not valid, since I now actually wake earlier than I am supposed to. The extra 10 minutes can actually lead to a disorientation with time.
The formula for centripetal acceleration, a, is given below, where v is the velocity of the object and r is the object's distance from the center of the circular path.
Answer:2/3-4
Step-by-step explanation:
Hi,
The correct answer is √ra = v or v = √ra.
The original equation is a = v^2/r.
Then we multiply r to get ra = v^2
After that we √ra = √v^2
Our final answer is then √ra = v
XD
Complete the table.PLSSS HELP ILL GIVE BRAINLIEST.PLS PLS PLS PLS
Answer:
0, 22, 44, 66
Step-by-step explanation:
Given the equation for the model, [tex] d = 11t [/tex] , you can complete the table above by simply plugging in each value of "t" has given in the table to solve for "d".
*When t (seconds) = 0, distance (feet) would be:
[tex] d = 11(0) [/tex]
[tex] d = 0 [/tex]
*When t (seconds) = 2, distance (feet) would be:
[tex] d = 11(2) [/tex]
[tex] d = 22 [/tex]
*When t (seconds) = 4, distance (feet) would be:
[tex] d = 11(4) [/tex]
[tex] d = 44 [/tex]
*When t (seconds) = 6, distance (feet) would be:
[tex] d = 11(6) [/tex]
[tex] d = 66 [/tex]
An 8 foot square floor is to be covered with square tiles measuring 8 inches on each side. If each tile
costs 50 cents, how much will it cost to tile the floor?
A. $32
B. $64
C. $72
D. $96
Please explain how to get the answer
Answer:
72
Step-by-step explanation:
There are 12 inches in a foot.
Therefore in 8 feet there are 96 inches
Therefore the square floor is 96 * 96.
Therefore the area of the square floor is 9216 inches squared.
Each tile is 8 inches by 8 inches meaning it has an area of 64 inches squared.
9216 / 64 = 144.
Therefore 144 tiles are needed to tile the floor
Since each tile is 50 cents, 144 * 0.5 = 72
Therefore it costs 72 dollars to tile the floor.
a small business had a total revenue of $51600. If this is 29% more than their total revenue the previous year, what was their total revenue the previous year?
What is the inverse of the logarithmic function
f(x) = log2x?
f –1(x) = x2
f –1(x) = 2x
f –1(x) = logx2
f –1(x) = StartFraction 1 Over log Subscript 2 Baseline x EndFraction
Answer:
B. edge 2021
B. is correct for the next one too.
Step-by-step explanation:
B. is the correct answer for the first one
B. is also the correct answer for the second one
In order to sustain itself in its cold habitat, a Siberian tiger requires 25 pounds of meat per day.
How much meat would seven Siberian tigers need for the month of April?
Select one:
a. 750 pounds
b. 175 pounds
c. 5425 pounds
d. 5250 pounds
Answer:
d. 5250 pounds
Step-by-step explanation:
25 lbs per day
There are 30 days in april
25 lbs/ day * 30 days
1 tiger would eat 750 lbs
There are 7 tigers
7 * 750 =5250 lbs
Answer:
D. 5250 pounds
Step-by-step explanation:
What you need to do is multiply 25 pounds by 30 because there are 30 days in the month of April.
25 x 30 = 750
Then multiply that amount by seven because there are 7 tigers.
750 x 7 = 5250
What is the volume of the cylinder below? Use the formula V = πr²h
Answer:
[tex]\boxed{V = 339.12 ft^3}[/tex]
Step-by-step explanation:
V = [tex]\pi r^2 h[/tex]
Where r = 3, h = 12
V = (3.14)(3)²(12)
V = (3.14)(9)(12)
V = 339.12 ft³