hellllllllllllllp me
Answer:
the probability is a fraction or a percentage, some times even a decimal
A sample of a radioactive substance decayed to 97% of its original amount after a year. (Round your answers to two decimal places.) (a) What is the half-life of the substance
Answer:
23 years
Step-by-step explanation:
Step 1: Calculate the rate constant (k) for the radioactive decay
A radioactive substance with initial concentration [A]₀ decays to 97% of its initial amount, that is, [A] = 0.97 [A]₀, after t = 1 year. Considering first-order kinetics, we can calculate the rate constant using the following expression.
ln [A]/[A]₀ = - k.t
k = ln [A]/[A]₀ / -t
k = ln 0.97 [A]₀/[A]₀ / -1 year
k = 0.03 year⁻¹
Step 2: Calculate the half-life of the substance
We will use the following expression.
[tex]t_{1/2}[/tex] = ln2/ k = ln 2 / 0.03 year⁻¹ = 23 years
4 statistics professors and 6 chemistry professors are available to be advisors to a student organization. The student organization needs two of the professors to be advisors. If each professor has an equal chance of being selected, what is the probability that both professors are chemistry professors?
the angles of a quadrilateral are 5x-30, 4x+60, 60-x and 3x+61.find the smallest of these angles
Answer:
60–x (smaller )
Step-by-step explanation:
Sum of all 4 angles of a quadrilateral = 360°
(5x-30) + (3x + 60) + (60-x) +(4x+ 50) = 360°
(12x - x) + ( 170 - 30) = 360°
11x + 140 = 360°
11x = 360 - 140 = 220
x = 220/11 = 20°
Each angles is :
5x - 30 = 100 - 30 = 70°
3x+ 60 = 60 + 60 = 120°
60 - x = 60 - 20 = 40°
4x + 50 = 80 + 50 = 130°
Smallest of these angles is 40°
Which one has infinity many solutions
Answer:
The correct options are:
3x - 4y = 15
15x - 20y = 75
(fourth option, counting fom the top)
5x + 6y = 20
-10x - 12y = -40
(last option)
Step-by-step explanation:
A system of linear equations has infinitely many solutions if and only if both equations define the same line.
Then we need to see which option describes twice the same line.
From the given options, the two with infinitely many solutions are:
3x - 4y = 15
15x - 20y = 75
How we check that? remember that we can multiply (or divide) both sides of an equation by the same number, and the equation remains unchanged.
So, if we take the first equation and multiply both sides by 5, we get:
5*(3x - 4y) = 5*15
15x - 20y = 75
Which is the same as the other equation, so both equations describe the same line.
The other system is the last one:
5x + 6y = 20
-10x - 12y = -40
If we take the first equation and multiply both sides by -2, we get:
-2*(5x + 6y) = -2*20
-10x - 12y = -40
So, again, both equations describe the same line.
What is the length of side s of the square shown below?
45*
8
90*
Answer is 4v2
Answer:
4 squareroot 2
Step-by-step explanation:
The answer is 4 squareroot 2
what is the volume explain why will mark branniest GIVE ME EXPLANATION
Answer:
63 yd³
Step-by-step explanation:
V = lwh
V = 7 × 3 × 9
V = 189
Since the cubes are 1/3 yd³, you now multiply the volume of this figure which is if it were a 1 yd³.
189 × [tex]\frac{1}{3}[/tex]
63 yd³
Question 6 of 10
62
A
59°
59
Triangle A
Triangle B
Given the triangles above, what is the measure, in degrees, of angler?
Find the point below that lies on the line y - 6 = 3(x-5).
O A. (5,6)
O B. (1,-5)
O C. (6,5)
O D. (4, -3)
O E. (3,-1)
Find the surface area of the prism.
Answer:
108 cm²
Step-by-step explanation:
the surface area is the sum of all individual shapes areas on the surface.
2 right-angled triangles
3 rectangles
area of a right-angled triangle is At = a×b/2
At = 4×3/2 = 6 cm²
we need it twice : 12 cm²
one rectangle (length×width) = 8×3 = 24 cm²
one rectangle = 8×4 = 32 in²
one rectangle = 8×5 = 40 cm²
total surface area
A = 12+24+32+40 = 108 cm²
an area is always a square unit (power of 2).
a volume is always a cubic unit (power of 3).
and a length is always a simple unit (power of 1).
determine using pascal's method. (2p-3q)^5=(p-q)^5
A running track has two semi-circular ends with radius 29m and two straights of length 91.3m as shown.
Calculate the total distance around the track rounded to 1 DP.
Answer:
Step-by-step explanation:
A health magazine reported that 27% of adult males smoke cigarettes. To test this claim, they select 40 adult males at random and record if they smoke cigarettes. They calculate a 95% confidence interval for the proportion of adult males who smoke and find it is 0.22 to 0.28
Answer:
Point estimate = 0.25
Step-by-step explanation:
Complete question
Calculate the point estimate
Solution
Let A represents the number of adult males who smoke cigarettes
Calculation of 95% confidence interval for proportion of adult males who smoke cigarettes
[tex]p-z_\alpha \frac{p(1-p)}{n}[/tex] , [tex]p+z_\alpha \frac{p(1-p)}{n}[/tex]
[tex]p-z_\alpha \frac{p(1-p)}{n} = 0.22\\p+z_\alpha \frac{p(1-p)}{n} = 0.28[/tex]
Point estimate
Adding the above given equations we get -
2 * p = 0.50
p = 0.25
Convert 25 miles into kilometres
Answer:
1 miles= 1.609km
so, 25x1.609 = 40.225km
Simplify please (: !
Answer:
[tex]\frac{a^2^0b^5}{c^5d^3^0}[/tex]
Step-by-step explanation:
When one raises a value to an exponent, one can multiply the current value of the exponent by the number it is raised to. This is the case because raising a value to an exponent is another way of representing that value times itself the number of times that the exponent indicates. Remember, if no exponent is written, then the exponent is (1).
One can apply this here by multiplying every exponent in this problem by (5) since the fraction is raised to the power (5).
[tex](\frac{a^4b}{cd^6})^5[/tex]
[tex]=\frac{(a^4^*^5)(b^1^*^5)}{(c^1^*^5)(d^6^*^5)}[/tex]
Simplify,
[tex]=\frac{a^2^0b^5}{c^5d^3^0}[/tex]
You play a game where you first choose a positive integernand thenflip a fair coinntimes. You win a prize if you get exactly 2 heads. How should youchoosento maximize your chance of winning
Solution :
The probability of winning when you choose n is = [tex]$^nC_2\left(\frac{1}{2}\right)^n$[/tex]
[tex]$n\left(\frac{n-1}{2}\right)\times \left(\frac{1}{2}\right)^n = n(n-1)\left(\frac{1}{2}\right)^{n+1}$[/tex]
Apply log on both the sides,
[tex]$f(n) = \log\left((n)(n-1)\left(\frac{1}{2}\right)^{n-1}\right) = \log n +\log (n-1)+(n+1) \ \log\left(\frac{1}{2}\right)$[/tex]
Differentiation, f(x) is [tex]$f'=\frac{1}{x}+\frac{1}{(x-1)}+\log\left(\frac{1}{2}\right)$[/tex]
Let us find x for which f' is positive and x for which f' is negative.
[tex]$\frac{1}{x}+\frac{1}{(x-1)} > 0.693$[/tex] , since [tex]$\log(1/2) = 0.693147$[/tex]
For x ≤ 3, f' > 0 for [tex]$\frac{1}{x}+\frac{1}{x-1}+\log\left(\frac{1}{2}\right)>0$[/tex]
[tex]$\frac{1}{x}+\frac{1}{x-1}-0.6931470$[/tex]
That means f(x) is increasing function for n ≤ 3
[tex]$\frac{1}{x}+\frac{1}{x-1}< 0.693147 $[/tex] for x > 4
f' < 0 for n ≥ 4, that means f(n) is decreasing function for n ≥ 4.
Probability of winning when you chose n = 3 is [tex]$3(3-1)\left(\frac{1}{2}\right)^{3+1}=0.375$[/tex]
Probability of winning when you chose n = 4 is [tex]$4(4-1)\left(\frac{1}{2}\right)^{4+1}=0.375$[/tex]
Therefore, we should chose either 3 or 4 to maximize chances of winning.
The probability of winning with an optimal choice is n = 0.375
1
15
3x =
2
Circle the ratio
xiy
6:1
1:6
3:2
2:3
Question isnt well formatted :
Answer:
1 : 6
Step-by-step explanation:
Given the question :
3x = 1/2y
3x = y/2
Multiply both sides by 2
3x * 2 = y/2 * 2
6x = y
This can be interpreted as :
y = 6 times the value of x
x = y/6
x : y
1 : 6
a two digit number has the following properties. If you add the digits together and multiply the result by 10, you will get 9 more than the reverse number? FInd all the possibilities
Answer:
10, 11, 12, 13, 14, 15, 16, 17, 18, 19
Step-by-step explanation:
A two-digit number can be written as:
a*10 + b
Where a and b are single-digit numbers.
a is the tens digit
b is the units digit.
the reverse number is:
b*10 + a
We know that:
"If you add the digits together and multiply the result by 10, you will get 9 more than the reverse number"
Then:
(a + b)*10 = b*10 + a + 9
We now need to solve this for a and b, where the other restriction that we have is that a and b can be any whole number of the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
Then:
(a + b)*10 = b*10 + a + 9
a*10 + b*10 = b*10 + a + 9
subtracting b*10 in both sides, we get:
a*10 = a + 9
solving this for a, we get:
a*10 - a = 9
a*(10 - 1) = 9
a*9 = 9
a = 9/9
a = 1
and notice that we do not have any restriction for b. So b can be any number of the set.
for example, if b = 2
a*10 + b = 12
now let's test the property:
10*(1 + 2) = 2*10 + 1 + 9
30 = 20 + 10 = 30
now if b = 4, we have:
a*10 + b = 1*10 + 4 = 14
10*(1 + 4) = 4*10 + 1 + 9
50 = 50
So we can see that for any value of b, this will work.
So the only restriction that we have, is that a must be equal to 1.
Then the numbers are:
10, 11, 12, 13, 14, 15, 16, 17, 18, 19
The possible numbers are 10, 11, 12, 13, 14, 15, 16, 17, 18 and 19
Assume the digits of the two-digit number are x and y, where:
x represents the tensy represents the unitsSo, the original number (n) is:
[tex]n = 10 \times x + y[/tex]
When the digits are added, and multiplied by 10, we have the following equation:
[tex](x + y) \times 10 = 9 + (y \times 10 + x)[/tex]
Expand the equation
[tex]10x + 10y = 9 + (10y + x)[/tex]
Remove bracket
[tex]10x + 10y = 9 + 10y + x[/tex]
Subtract 10y from both sides
[tex]10x = 9 + x[/tex]
Subtract x from both sides
[tex]9x = 9[/tex]
Divide both sides by 9
[tex]x = 1[/tex]
Recall that the number is represented as:
[tex]n = 10 \times x + y[/tex]
So, we have:
[tex]n = 10 \times 1 + y[/tex]
[tex]n = 10 + y[/tex]
This means that, the possible numbers are from 10 to 19
Read more about two-digit numbers at:
https://brainly.com/question/23846183
PLS PLS PLS I NEED HELP
Given * inserted picture* find
Answer:
SinA=5/1 3 CosA=12/13 tanA=5/12. SinC=12/13 CosC=5/13 and tanC=12/5
Step-by-step explanation:
Basically find the third side by Pythagorean theorem which would get you 13. So 13 is the hypotenuse. Remember these 3 formulas. Sin=Opposite/Hypotenuse Cos=Adjacent/hypotenuse and Tan=opposite/Adjacent. So for Sin a the opposite side to angle A is 5. The hypotenuse is always the same which would be 13. So Sin a is 5/13. For cos the side adjacent would be 12. So it is 12/13. *Note Hypotenuse cannot be considered the adjacent.
Answer:
sin A = 5/13, cos A = 12/13, tan A = 5/12, sin C = 12/13, cos C = 5/13, tan C = 12/5
Step-by-step explanation:
According to Pythagoras, hypotenuse = √{(12)^2+(5)^2}. So, hypotenuse = 13. (See picture if confused).
sin A = 5/13
cos A = 12/13
tan A = 5/12
sin C = 12/13
cos C = 5/13
tan C = 12/5
Jon earns $3 for every package he wraps. To take a package to the post office, Jon earns 1.65 times as much as he earns for wrapping a package. How much will Jon earn for wrapping a package and taking it to the post office?
Answer:
a1 = 1, a2 = 2Step-by-step explanation:
Which of thw following is a result of shifting circle with!!
Answer:
I need more information to answer this
If f(x) = x + 1, and g(x) = 2x,
then
f(g(x)) = [ ? ]x + [ ]
Answer:
2x+1
Step-by-step explanation:
f(g(x))= (2x)+1
(2)x+1
After selling your house and purchasing a new house you have $25,000 left you wish to invest. The first
option you have is a one year T-Bill with a par value of $25,000 which costs $23,250. Your second option
is to invest in a 12 month CD with a 6.5% interest rate. Of these two available options which would allow you to receive a higher rate of return.
Answer:
Of course CD is higher then investing in T-bill
Simplify the expression using trigonometric identities (csc θ – csc θ · cos^2 θ).
options:
A)
sin^2 θ
B)
sin θ · tan θ
C)
sin^3 θ
D)
sin θ
Answer:
Solution given:
cscθ -cscθcos²θ
taking common
cscθ(1-cos²θ)
we have
1-cos²θ=sin²θ and cscθ=1/sinθ
now
1/sinθ*sin²θ
=sinθ
so
D)
sin θ is a required answer.
Hamdan says that when you add fractions with the same denominator, you can add the numerators and keep the same denominator. Is Hamdan correct?
Answer:
Yes, Hamdan is correct.
Step-by-step explanation:
Let the two fractions are q/r and s/r.
Here, the denominator is same for both the fractions.
So, as we add them, add the numerators and the denominators remains same.
[tex]\frac{q}{r}+\frac{s}{r}\\\\=\frac{q + s}{r}[/tex]
For example
[tex]\frac{3}{5}+\frac{4}{5}\\\\=\frac{3 + 4}{5}\\\\=\frac{7}{5}[/tex]
So, Hamdan is correct.
∠DEF and ∠FEG are supplementary. m∠DEF=(3x+5)°, and m∠FEG=(2x)°. What is the measure of ∠DEF?
Answer:
DEF = 110
Step-by-step explanation:
Supplementary angles add to 180
3x+5 +2x = 180
Combine like terms
5x +5 = 180
Subtract 5 from each side
5x = 175
Divide each side by 5
5x/5 = 175/5
x =35
DEF = 3x+5
= 3*35 +5
= 105+5
= 110
Question in the image
Answer:
1/6
is the probability
ok
Find X. Round your answer to the nearest TENTH of a degree. (GIVING BRAINLEST)
Answer:
36.8 i think
Step-by-step explanation:
For vectors u = i + 6j, v = 5i – 3j, and w = 9i – 2j, determine u • w + v • w.
27
18
90
48
Answer:
This is the explanation you can find answer by rolling it.Find the length of the diagonal of a rectangle. Round your answer to nearest tenth.
Answer:
19.2m
Step-by-step explanation:
"Slice" the rectangle into two right triangles (slice along the diagonal). Now you can use the Pythagorean theorem to calculate the length of the diagonal:
[tex]a^{2} +b^{2} =c^{2} \\12^{2}+15^{2} =c^{2} \\144+225=c^{2} \\\sqrt{369} =\sqrt{c^{2} }\\19.2m =c[/tex]