Answer:
Area = 18 square units
Step-by-step explanation:
To find the area of the triangle, let's go through the following steps:
(i) Let the vertices be;
A = (7, -3)
B = (4, -3)
C = (4, 9)
(ii) The sides of the triangle are therefore,
AB, BC and CA
(iii) Using the distance formula, calculate the lengths of AB, BC and CA
[tex]AB = \sqrt{(7-4)^2 + ( -3 - (-3))^2}[/tex]
[tex]AB = \sqrt{3^2 + (0)^2}\\[/tex]
[tex]AB = \sqrt{9}[/tex]
[tex]AB = 3[/tex]
[tex]BC = \sqrt{(4-4)^2 + ( -3 - 9)^2}[/tex]
[tex]BC = \sqrt{0^2 + (-12)^2}[/tex]
[tex]BC = \sqrt{144}[/tex]
[tex]BC = 12[/tex]
[tex]CA = \sqrt{(4-7)^2 + ( 9 - (-3))^2}[/tex]
[tex]CA = \sqrt{(-3)^2 + (12)^2}[/tex]
[tex]CA = \sqrt{9 + 144}[/tex]
[tex]CA = \sqrt{153}[/tex]
[tex]CA = 12.4[/tex]
(iv) Now that we have all the sides, let's calculate the area of the triangle using the Heron's formula.
Area = [tex]\sqrt{p(p-a)(p-b)(p-c)}[/tex]
Where;
p = [tex]\frac{a + b + c}{2}[/tex]
a, b and c are the sides of the triangle.
In our case,
let
a = AB = 3
b = BC = 12
c = CA = 12.4
∴ p = [tex]\frac{3 + 12 + 12.4}{2}[/tex]
p = 13.7
Area = [tex]\sqrt{p(p-a)(p-b)(p-c)}[/tex]
Area = [tex]\sqrt{13.7(13.7-3)(13.7-12)(13.7-12.4)}[/tex]
Area = [tex]\sqrt{13.7(10.7)(1.7)(1.3)}[/tex]
Area = [tex]\sqrt{323.9639}[/tex]
Area = 17.999
Area = 18 square units
OR
To get the area of the triangle, we can use a much simpler approach.
Since the triangle is a right triangle,
(i) the hypotenuse, which is the longest side is CA = 12.4
(ii) the other two sides are AB and BC. These two sides will form the right angle.
Therefore, we can use the relation:
Area = [tex]\frac{1}{2}[/tex] x base x height
Where;
the base or height can either be AB or BC
Area = [tex]\frac{1}{2}[/tex] x 3 x 12
Area = 18 square units
PS: In a right triangle, the other two sides apart from the hypotenuse form the right angle.
There are 2229 students in a school district. Among a sample of 452 students from this school district, 163 have mathematics scores below grade level. Based on this sample, estimate the number of students in this school district with mathematics scores below grade level.
a. 804
b. 844
c. 884
d. 0.36
Answer:
A. 804Step-by-step explanation:
Given the total number of students in the school to be 2229 students. If among a sample of 452 students from this school district, 163 have mathematics scores below grade level, then we can determine the number of students in this school district with mathematics scores below grade level based on the sample scores using ratio.
Let the number of students in this school district with mathematics scores below grade level be x. The ratio of the students with math score below grade level to total population will be x:2229
Also, the ratio of the sample students with math score below grade level to sample population will be 163:452
On equating both ratios, we will have;
x:2229 = 163:452
[tex]\dfrac{x}{2229} = \dfrac{163}{452}\\ \\cross\ multiplying;\\\\\\452*x = 2229*163\\\\x = \dfrac{2229*163}{452}\\ \\x = \frac{363,327}{452}\\ \\x = 803.8\\\\x \approx 804[/tex]
Hence the estimate of the number of students in this school district with mathematics scores below grade level based on the sample is 804
An octagonal pyramid ... how many faces does it have, how many vertices and how many edges? A triangular prism ... how many faces does it have, how many vertices and how many edges? a triangular pyramid ... how many faces does it have, how many vertices and how many edges?
1: 8 faces and 9 with the base 9 vertices and 16 edges
2: 3 faces and 5 with the bases 6 vertices and 9 edges
3: 3 faces and 4 with the base 4 vertices and 6 edges
Hope this can help you.
Factor.
x2 + 11x
x2 + 11x
x(x + 11)
11(x + 11)
0(x2 + 11x)
Answer:
x(x + 11)
Step-by-step explanation:
x^2 + 11x when factored gives a result of x(x + 11)
Answer:
x(x+11)
Step-by-step explanation:
We are given the expression:
[tex]x^2+11x[/tex]
This can be factored using the Greatest Common Factor (GCF).
The GCF of x^2 and 11x is x.
Factor out an x.
[tex]x(x+11)[/tex]
x^2+11x factored is: x(x+11).
A technician is testing light bulbs to determine the number of defective bulbs. The technician records the table below to show the results. Result of Light Bulb Test Number of Bulbs Tested 14 28 84 336 Number of Defective Bulbs Found 1 2 6 ? The technician expects to find 24 defective bulbs when 336 are tested. Which statement explains whether the technician’s reasoning is correct, based on the information in the table?
Answer:
He should find 24 defective lightbulbs.
Step-by-step explanation:
1. Divide the number of defective bulbs by the total number of bulbs for each section.
2. Make sure the number you get is the same each time.
3. Divide the guessed number of bulbs (24) by the total number of bulbs (336)
4. If the number you got for step 4 matches the number you got for step 3, then he is right
Answer:
The answer is A
Step-by-step explanation:
on NCCA
How many different sets of polar coordinates can be given for a point, within one rotation? I thought it was infinite, but the given options are 1, 2, 3, and 4.
Answer:
the answer is 4
Step-by-step explanation:
so 1 rotation is like a circle 1 unit circle requires 4 quadrant to be in this is the most simplified i can get
Answer:
Solution : 4
Step-by-step explanation:
The question asks us how many polar coordinates are possible for one rotation. For one rotation there will be 4 polar coordinates, one present in each quadrant such that,
( r, theta ), ( r, theta ), ( - r, theta ), ( - r, theta )
Respectively if theta was q say,
( r, q ), ( r, - q ), ( - r, q ), ( - r, -q )
Therefore there are 4 sets of polar coordinates for one rotation, in each of the 4 quadrants.
What is the area of a parallelogram if the coordinates of its vertices are (0, -2), (3,2), (8,2), and (5, -2)?
Answer: 20 sq. units .
Step-by-step explanation:
Let A(0, -2), B(3,2), C(8,2), and D(5, -2) are the points for the parallelogram.
First we plot these points on coordinate plane, we get parallelogram ABCD.
By comparing the y-coordinate of B and C with A and D , we get
height = 2+2 = 4 units
Also by comparing the x coordinates of A and D, we get base = 5-0= 5 units
Area of parallelogram = Base x height
= 5 x 4 = 20 sq. units
Hence, the area of a parallelogram ABCD is 20 sq. units .
Consider the following functions. f={(−1,1),(1,−2),(−5,−1),(5,3)} and g={(0,2),(−3,−4),(1,−2)} Step 1 of 4: Find (f+g)(1).
Answer:
-4
Step-by-step explanation:
(f+g)(1) = f(1) +g(1)
In each case, you need to locate the ordered pair with 1 as the first element.
(1, f(1)) = (1, -2) . . . . f(1) = -2
(1, g(1)) = (1, -2) . . . . g(1) = -2
f(1) +g(1) = (-2) +(-2) = -4
(f+g)(1) = -4
Aaron wants to mulch his garden. His garden is x^2+18x+81 ft^2 One bag of mulch covers x^2-81 ft^2 . Divide the expressions and simplify to find how many bags of mulch Aaron needs to mulch his garden.
Answer:
Step-by-step explanation:
Given
Garden: [tex]x^2+18x+81[/tex]
One Bag: [tex]x^2 - 81[/tex]
Requires
Determine the number of bags to cover the whole garden
This is calculated as thus;
[tex]Bags = \frac{x^2+18x+81}{x^2 - 81}[/tex]
Expand the numerator
[tex]Bags = \frac{x^2+9x+9x+81}{x^2 - 81}[/tex]
[tex]Bags = \frac{x(x+9)+9(x+9)}{x^2 - 81}[/tex]
[tex]Bags = \frac{(x+9)(x+9)}{x^2 - 81}[/tex]
Express 81 as 9²
[tex]Bags = \frac{(x+9)(x+9)}{x^2 - 9\²}[/tex]
Evaluate as difference of two squares
[tex]Bags = \frac{(x+9)(x+9)}{(x - 9)(x+9)}[/tex]
[tex]Bags = \frac{(x+9)}{(x - 9)}[/tex]
Hence, the number of bags is [tex]Bags = \frac{(x+9)}{(x - 9)}[/tex]
A potato chip company makes potato chips in two flavors, Regular and Salt & Vinegar. Riley is a production manager for the company who is trying to ensure that each bag contains about the same number of chips, regardless of flavor. He collects two random samples of 10 bags of chips of each flavor and counts the number of chips in each bag. Assume that the population variances of the number of chips per bag for both flavors are equal and that the number of chips per bag for both flavors are normally distributed. Let the Regular chips be the first sample, and let the Salt & Vinegar chips be the second sample. Riley conducts a two-mean hypothesis test at the 0.05 level of significance, to test if there is evidence that both flavors have the same number of chips in each bag. (a) H0:μ1=μ2; Ha:μ1≠μ2, which is a two-tailed test. (b) t≈1.44 , p-value is approximately 0.167 (c) Which of the following are appropriate conclusions for this hypothesis test?
A. There is insufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag.B. There is sufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag.C. Reject H0.D. Fail to reject H0.
Answer:
A. There is insufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag.
D. Fail to reject H0.
Step-by-step explanation:
From the summary of the given test statistics.
The null and the alternative hypothesis are:
[tex]H_0:\mu_1=\mu_2 \\ \\ Ha:\mu_1 \neq \mu_2[/tex]
This test is also a two tailed test.
Similarly, the t value for the test statistics = 1.44
The p- value - 0.167
The level of significance ∝ = 0.05
The objective we are meant to achieve here is to determine which of the following from the given options are appropriate conclusions for this hypothesis test.
From what we have above:
Decision Rule: We fail to reject the null hypothesis since the p-value is greater than the level of significance at 0.05
CONCLUSION: Therefore, we can conclude that there is insufficient evidence at the 0.05 level of significance to conclude that Regular and Salt & Vinegar chips have different amounts of chips per bag as we fail to reject H0.
Five more than the square of a number Five more than twice a number Five less than the product of 3 and a number Five less the product of 3 and a number Twice the sum of a number and 5 The sum of twice a number and 5 The product of the cube of a number and 5 The cube of the product of 5 and a number. 5 + x2 5 + 2x 5 - 3x 3x - 5 2x + 5 2(x + 5) 5x3 (5x)3 WILL MARK BRAINLIEST AND DON'T PUT A FAKE ANSWER TO GET POINTS EITHER CUS I NEED HELP
Answer:
BelowStep-by-step explanation: Let all unknown no be x
Five more than the square of a number
= [tex]5 + x^2[/tex]
Five more than twice a number ;
[tex]5+2x\\= 2x+5[/tex]
Five less than the product of 3 and a number ;
[tex]5- 3x\\= 3x-5[/tex]
Twice the sum of a number and 5 ;
[tex]2(x+5)\\[/tex]
The sum of twice a number and 5 ;
[tex]2x+5[/tex]
The product of the cube of a number and 5;
[tex]x^3 \times 5\\=5x^3[/tex]
The cube of the product of 5 and a number ;
[tex](5\times x)^3\\(5x)^3[/tex]
. In statistics, a data set has the following characteristics: (Choose all that apply) A:A data set is a collection of similar data. B:A data set can contain only quantitative data. C:A data set is any piece of descriptive or quantitative information on any object of study. D:A data set contains data all of which have some common characteristic.
Answer:
A. A data set is a collection of similar data.
D. A data set contains data all of which have some common characteristic.
Based on the dot plots shown in the images, which of the following is a true statement? A. Set B has the greater mode. B. Set A has more items than set B. C. Set A is more symmetric than set B. D. Set B has the greater range.
Assume that women's heights are normally distributed with a mean given by mu = 64.3 inches, and a standard deviation given by sigma= 2.2 inches.
A) If a woman is randomly selected, find the probability that her height is less than 65 inches.
B) If 34 women are randomly selected, find the probability that they have a mean height less than 65 inches.
Answer:69
Step-by-step explanation:
what number has 7 ten thousands, 1 thousand, 1 hundred, and no ones?
Answer:
[tex]71,100[/tex]
Step-by-step explanation:
If you are trying to find a number that is written in word form, we can just use place values to find what goes where.
A number is broken down into this:
Ten thousands, thousands, hundreds, tens, ones.
If they have 7 ten thousands, the first digit will be a 7.
If they have 1 thousand, the second digit will be a 1.
If they have 1 hundred, the third digit will be a 1.
Since nothing is stated about tens, we assume it's value is 0.
And since there are no ones, it's value is 0.
So:
71,100.
Hope this helped!
What is the slope of the line that passes through (2, 12) and (4, 20)?On the graph of the equation 3x + 2y = 18, what is the value of the y-intercept?
Answer: The slope of the line that passes through (2, 12) and (4, 20) is 4.
The value of the y-intercept is 9.
Step-by-step explanation:
Slope of line passing through (a,b) and (c,d) = [tex]\dfrac{d-b}{c-a}[/tex]
Then, the slope of the line that passes through (2, 12) and (4, 20) = [tex]\dfrac{20-12}{4-2}[/tex]
[tex]=\dfrac{8}{2}=4[/tex]
So, the slope of the line that passes through (2, 12) and (4, 20) is 4.
To find the y-intercept of 3x + 2y = 18, first write in slope intercept form y=mx+c ( where c= y-intercept ).
[tex]2y=-3x+18\\\\\Rightarrow\ y=-\dfrac{3}{2}x+9[/tex]
By comparison, c= 9
Hence, the value of the y-intercept is 9.
PLS HELP ASAP Solve the inequality and enter your solution as an inequality in the box below 8>4-x>6
Answer:
−4<x<−2
Step-by-step explanation:
8 > 4 − x > 6
8 > −x + 4 > 6
8 + −4 > −x + 4 + −4 > 6 + −4
4 > −x > 2
Since x is negative we need to divide everything by -1 which gives us...
−4 < x < −2
Consider the following. x = t − 2 sin(t), y = 1 − 2 cos(t), 0 ≤ t ≤ 2π Set up an integral that represents the length of the curve. 2π 0 dt Use your calculator to find the length correct to four decimal places.
Answer:
L = 13.3649
Step-by-step explanation:
We are given;
x = t − 2 sin(t)
dx/dt = 1 - 2 cos(t)
Also, y = 1 − 2 cos(t)
dy/dt = 2 sin(t)
0 ≤ t ≤ 2π
The arc length formula is;
L = (α,β)∫√[(dx/dt)² + (dy/dt)²]dt
Where α and β are the boundary points. Thus, applying this to our question, we have;
L = (0,2π)∫√((1 - 2 cos(t))² + (2 sin(t))²)dt
L = (0,2π)∫√(1 - 4cos(t) + 4cos²(t) + 4sin²(t))dt
L = (0,2π)∫√(1 - 4cos(t) + 4(cos²(t) + sin²(t)))dt
From trigonometry, we know that;
cos²t + sin²t = 1.
Thus;
L = (0,2π)∫√(1 - 4cos(t) + 4)dt
L = (0,2π)∫√(5 - 4cos(t))dt
Using online integral calculator, we have;
L = 13.3649
How would you simplify and rationalize this expression? [tex]\frac{5\sqrt[4]{2}}{4\sqrt[4]{162} }[/tex]
Answer:
5/12
Step-by-step explanation:
(5 * 2^1/4)/4 * 162^1/4) = (5 * 2^1/4)/4 * 3 *2^1/4)
multiply top and bottom by 2^3/4
(5 * 2)/4 * 3 * 2) = 10/24 = 5/12
Fiona wrote the linear equation y = y equals StartFraction 2 over 5 EndFraction x minus 5.x – 5. When Henry wrote his equation, they discovered that his equation had all the same solutions as Fiona’s. Which equation could be Henry’s? x – x minus StartFraction 5 over 4 EndFraction y equals StartFraction 25 over 4 EndFraction.y = x – x minus StartFraction 5 over 2 EndFraction y equals StartFraction 25 over 4 EndFraction.y = x – x minus StartFraction 5 over 4 EndFraction y equals StartFraction 25 over 2 EndFraction.y = x – x minus StartFraction 5 over 2 EndFraction y equals StartFraction 25 over 2 EndFraction.y =
Answer:
D. [tex]x-\frac{5}{2}y = \frac{25}{2}[/tex]
Step-by-step explanation:
Given
[tex]y = \frac{2}{5}x - 5[/tex]
Required
Determine its equivalent
From the list of given options, the correct answer is
[tex]x - \frac{5}{2}y = \frac{25}{2}[/tex]
This is shown as follows;
[tex]y = \frac{2}{5}x - 5[/tex]
Multiply both sides by [tex]\frac{5}{2}[/tex]
[tex]\frac{5}{2} * y = \frac{5}{2} * (\frac{2}{5}x - 5)[/tex]
Open Bracket
[tex]\frac{5}{2} * y = \frac{5}{2} * \frac{2}{5}x - \frac{5}{2} *5[/tex]
[tex]\frac{5}{2}y = x - \frac{25}{2}[/tex]
Subtract x from both sides
[tex]\frac{5}{2}y - x = x -x - \frac{25}{2}[/tex]
[tex]\frac{5}{2}y - x = - \frac{25}{2}[/tex]
Multiply both sides by -1
[tex]-1 * \frac{5}{2}y - x * -1 = - \frac{25}{2} * -1[/tex]
[tex]-\frac{5}{2}y + x = \frac{25}{2}[/tex]
Reorder
[tex]x-\frac{5}{2}y = \frac{25}{2}[/tex]
Hence, the correct option is D
[tex]x-\frac{5}{2}y = \frac{25}{2}[/tex]
Answer:
The 4th option
Step-by-step explanation:
Which of the following is the correct set notation for the set of perfect squares between 1 and 100 (including 1 and 100)?
Select the correct answer below:
{p2∣p∈ℤ and 1≤p≤10}
{p2∣p∈ℤ and 1
Answer:
[tex]\{P^2: P\ E\ Z\ and\ 1\leq p\leq 10\}[/tex]
Step-by-step explanation:
Given
Range: = 1 to 100 (Inclusive)
Required
Determine the notation that represents the perfect square in the given range
Represent the range with P
P = 1 to 100
Such that the perfect squares will be P² and integers
In set notation, integers are represented with Z
The set notation becomes
[tex]\{P^2: P\ E\ Z\ and\ 1\leq p\leq 10\}[/tex]
The [tex]\leq[/tex] shows that 1 and 100 are inclusive of the set
The graph of g(x) = x – 8 is a transformation of the graph of f(x) = x. Which of
the following describes the transformation?
(A) translation 8 units down
(B) translation 8 units up
(C) translation 8 units right
(D) translation 8 units left
A clothing business finds there is a linear relationship between the number of shirts, n, it can sell and the price, p, it can charge per shirt. In particular, historical data shows that 1,000 shirts can be sold at a price of $30, while 3,000 shirts can be sold at a price of $10. Find a linear equation in the form p(n)=mn+b that gives the price p they can charge for n shirts.
Answer:
p(n) = -1/100 n 40
Step-by-step explanation:
Use the two points (n, p): (1000, 30) and (3000, 10).
Now we find the equation of the line that passes through these two points.
m = (10 - 30)/(3000 - 1000)
m = -20/2000
m = -1/100
p(n) = mn + b
30 = -1/100 * 1000 + b
30 = -10 + b
b = 40
The equation is:
p(n) = -1/100 n 40
Which statement best describes a sequence? a.All sequences have a common difference. b.A sequence is always infinite. c.A sequence is an ordered list. d.A sequence is always arithmetic or geometric.
Answer:
C
Step-by-step explanation:
A sequence is defined as a list of numbers or objects in a special order.
They may be arithmetic or geometric or neither.
For example
0, 1, 4, 9, 16, 25, ..... ← is the sequence of square numbers.
Note it is neither arithmetic or geometric.
These girts stasts jogging from the same point around
acircular track and they complete one round in 24
Seconds 36 seconds and 48 seconds respectively,
After.
how much time will they meet atone point?
Answer:
2hrs 24mins
Step-by-step explanation:
Very simple the time they will meet again at the point will be the LCM of their various time taken to complete a cycle.
Ans LCM(24, 36, 48) = 144 mins
= 2hrs 24mins
Answer:
The answer is 2 hours and 24 minutes
Step-by-step explanation:
Hope you get this right:)
A soda bottling company’s manufacturing process is calibrated so that 99% of bottles are filled to within specifications, while 1% is not within specification. Every hour, 12 random bottles are taken from the assembly line and tested. If 2 or more bottles in the sample are not within specification, the assembly line is shut down for recalibration. What is the probability that the assembly line will be shut down, given that it is actually calibrated correctly? Use Excel to find the probability. Round your answer to three decimal places.
Answer:
The probability that the assembly line will be shut down is 0.00617.
Step-by-step explanation:
We are given that a soda bottling company’s manufacturing process is calibrated so that 99% of bottles are filled to within specifications, while 1% is not within specification.
Every hour, 12 random bottles are taken from the assembly line and tested. If 2 or more bottles in the sample are not within specification, the assembly line is shut down for recalibration.
Let X = Number of bottles in the sample that are not within specification.
The above situation can be represented through binomial distribution;
[tex]P(X=r)=\binom{n}{r} \times p^{r}\times (1-p)^{n-r};x=0,1,2,3,.....[/tex]
where, n = number of trials (samples) taken = 12 bottles
x = number of success = 2 or more bottles
p = probabilitiy of success which in our question is probability that
bottles are not within specification, i.e. p = 0.01
So, X ~ Binom (n = 12, p = 0.01)
Now, the probability that the assembly line will be shut down is given by = P(X [tex]\geq[/tex] 2)
P(X [tex]\geq[/tex] 2) = 1 - P(X = 0) - P(X = 1)
= [tex]1-\binom{12}{0} \times 0.01^{0}\times (1-0.01)^{12-0}-\binom{12}{1} \times 0.01^{1}\times (1-0.01)^{12-1}[/tex]
= [tex]1-(1 \times 1\times 0.99^{12})-(12 \times 0.01^{1}\times 0.99^{11})[/tex]
= 0.00617
Henry is investing at a continuously compounded annual interest rate of 4.5%. How many years will it take for the balance
to triple? Round your answer up to the nearest whole number, and do not include the units in your answer.
Answer:
1 year
Step-by-step explanation:
Hello,
Continuously compounding with an annual interest rate of 4.5% means multiplying the initial investment by (for t tears).
[tex]\displaystyle e^{(1+4.5\%)t}=e^{\left( 1.045\cdot t \right) }[/tex]
So we need to find t so that:
[tex]\displaystyle e^{\left( 1.045\cdot t \right) }=3\\\\1.0.45t=ln(3)\\\\t=\dfrac{ln(3)}{1.045}=1.051304...[/tex]
Rounding to the nearest whole number gives 1 year.
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
Answer:
25
Step-by-step explanation:
Trust me
I don't understand word problems can someone please answer it for me and I need it ASAP.
Answer:
Inequality: 3 + 1.2c
What you'd put on graph: 1 ≥ 13.50
A school newspaper reporter decides to randomly survey 15 students to see if they will attend Tet festivities this year. Based on past years, she knows that 24% of students attend Tet festivities. We are interested in the number of students who will attend the festivities.
Find the probability that at most 4 students will attend. (Round your answer to four decimal places.)
Answer:
0.70319018
Step-by-step explanation:
Given the following:
Number of students surveyed (n) = 15
Probability of attending tet festival (p) = 24% =0.24
Therefore,
Probability of not attending (1 - p) = (1 - 0.24) = 0.76.
The probability that at most 4 students will attend can be obtained using the binomial probability relation:
p(x) = nCx * p^x * (1 - p)^(n-x)
At most 4 students means:
p(x=0) + p(x=1) + p(x=2) + p(x=3) + p(x=4)
p(x=0) = 15C0 * 0.24^0 * 0.76^(15 - 0)
p(x=0) = 1 * 1 * 0.0004701 = 0.00047018
p(x=1) = 15C1 * 0.24^1 * 0.76^(14)
p(x=1) = 15 * 0.24 * 0.021448 = 0.07721
p(x=2) = 15C2 * 0.24^2 * 0.76^(13) =
p(x=2) = 105 * 0.0576 * 0.02822 = 0.17068
p(x=3) = 15C3 * 0.24^3 * 0.76^(12)
p(x=3) = 455 * 0.013824 * 0.037133 = 0.23356
p(x=4) = 15C4 * 0.24^4 * 0.76^(11) =
p(x=4) = 1365 * 0.0033177 * 0.048859 = 0.22127
0.00047018 + 0.07721 + 0.17068 + 0.23356 + 0.22127 = 0.70319018
Suppose that 80% of all registered California voters favor banning the release of information from exit polls in presidential elections until after the polls in California close. A random sample of 25 registered California voters is selected.
Required:
a. Calculate the mean and standard deviation of the number of voters who favor the ban.
b. What is the probability that exactly 20 voters favor the ban?
Answer:
a. Mean = 20
Sd = 4
b. Probability of X = 20 = 0.1960
Step-by-step explanation:
we have
n = 25
p = 80% = 0.8
mean = np
= 0.8 * 25
= 20
standard deviation = √np(1-p)
= √25*0.8(1-0.8)
=√4
= 2
probability that exactly 20 favours ban
it follows a binomial distribution
= 25C20 × 0.8²⁰ × 0.2⁵
= 53130 × 0.01153 × 0.00032
= 0.1960
Probability of X = 20 = 0.1960
Solve 5(2x + 4) = 15. Round to the nearest thousandth.
[tex]5(2x + 4) = 15\\10x+20=15\\10x=-5\\x=-\dfrac{5}{10}=-0,5[/tex]
Answer:
[tex]\huge\boxed{x=-0.5}[/tex]
Step-by-step explanation:
[tex]5(2x+4)=15\qquad\text{divide both sides by 5}\\\\\dfrac{5\!\!\!\!\diagup(2x+4)}{5\!\!\!\!\diagup}=\dfrac{15\!\!\!\!\!\diagup}{5\!\!\!\!\diagup}\\\\2x+4=3\qquad\text{subtract 4 from both sides}\\\\2x+4-4=3-4\\\\2x=-1\qquad\text{divide both sides by 2}\\\\\dfrac{2x}{2}=\dfrac{-1}{2}\\\\\boxed{x=-0.5}[/tex]
