Answer:
Step-by-step explanation:
Statement Solution
1. AB = CB Definition of isosceles triangle
2: AD = DC BD is the median to base AC
3. BD = BD Reflexive property
4. ΔADB ≅ ΔADC Side Side Side Congruent
which algebraic expression are equivalent to the phrase a number increased by 0.25 select all that apply
Answer:
number increased by ten. ... y = x + 0.25.
Step-by-step explanation:
Halla tres enteros consecutivos tales que 4 veces el entero del medio es 6 más que la suma del primero y el tercero
An article in Fire Technology, 2014 (50.3) studied the effectiveness of sprinklers in firecontrol by the number of sprinklers that activate correctly. The researchers estimate the probability of a sprinkler to activate correctly to be 0.7. Suppose that you are an inspector hired to write a safety report for a large ballroom with 10 sprinklers. Assume the sprinklers activate correctly or not independently.
Required:
a. What is the probability that all of the sprinklers will operate correctly in a fire?
b. What is the probability that at least 7 of the sprinklers will operate correctly in a fire?
c. What is the minimum number of sprinklers needed so that the probability that at least one operates correctly is at least 0.98?
Answer:
0.028 ; 0.649 ; 4
Step-by-step explanation:
P(correctly activation), p = 0.7
Number of sprinklers, n = 10
q = 1 - p = 1 - 0.7 = 0.3
Using the binomial probability relation :
P(x =x) = nCx * p^x * (1 - p)^(n - x)
Probability that all sprinklers activate correctly;
P(x = 10) = 10C10 * 0.7^10 * 0.3^0
P(x = 10) = 1 * 0.0282475249 * 1
P(x = 10) = 0.028
Probability that atleast 7 will operate correctly :
P(x ≥ 7) = p(x = 7) + p(x = 8) + p(x = 9) + p(x = 10)
P(x ≥ 7) = 0.267 + 0.233 + 0.121 + 0.028
P(x ≥ 7) = 0.649
3.)
Probability of atleast 1 operates :
P(x ≥ 1) = 0.98
1 - probability of 0 operates
1 - p(x =0)
P(x = 0) = nC0 * 0.7^0 * 0.3^n = 0.02
Recall :
nC0 = 1 ;
1 - p(x = 0)
P(x = 0) = 1 * 1 * 0.3^n = 0.02
0.3^n = 0.02 - - - (1)
0.3^3.24 = 0.02 - - - (2)
Comparing (1) and (2)
n = 3.24
Since, n cannot be a fraction ;
Then n is rounded to the next whole number = 4
The area (A) of a rectangle varies jointly as the length (l) and the width (w), and whose A = 60 sq. cm when l = 4 cm and w = 3 cm. What is the area of rectangle if the length is 6 cm and whose width is 3 cm?
Answer:
The area is 90 sq. cm
Step-by-step explanation:
Given
The variation can be represented as:
[tex]A\ \alpha\ l * w[/tex]
Area = 60, when l = 4 and w = 3
Required
Find Area, when l = 6 and w = 3
Represent the variation as an equation
[tex]A = k(l * w)[/tex]
Where k is the constant of variation.
Substitute 60 for A, 4 for l and 3 for w
[tex]60 = k * (4 * 3)[/tex]
[tex]60 = k * 12[/tex]
Make k the subject
[tex]\frac{60}{12} = k[/tex]
[tex]5=k[/tex]
[tex]k=5[/tex]
To get the value of Area when l = 6 and w = 3.
Substitute 5 for k, 6 for l and 3 for w in [tex]A = k(l * w)[/tex]
[tex]A = 5 * 6 * 3[/tex]
[tex]A = 90[/tex]
The area is 90 sq. cm
If money is invested for a short period of time, simple interest is paid using the following formula.
I = Prt
P is the money invested, or principal amount, r is the simple interest rate, and t is the time, in years, the money is invested.
Given P = $2,000, t = 2 years, and I = $280, what is the simple interest rate?
A. 7%
B. 0.7%
C. 8%
D. 0.07%
Answer:
A. 7%
Step-by-step explanation:
Given the following data;
Principal, P = $2,000
Time, T = 2 years
Simple Interest, I = $280
To find the simple interest rate, R?
Mathematically, simple interest is calculated using this formula;
[tex] S.I = \frac {PRT}{100} [/tex]
Where;
S.I is simple interest. P is the principal. R is the interest rate. T is the time.Substituting into the equation, we have;
[tex] 280 = \frac {2000*R*2}{100} [/tex]
Cross-multiplying, we have;
[tex] 280 * 100 = 4000*R[/tex]
[tex] 28000 = 4000R [/tex]
[tex] R = \frac {28000}{4000} [/tex]
Simple interest rate, R = 7%
23
Using the distance formula, d = √(x2 - x1)2 + (y2 - y1)2, what is the distance between point (0, 5) and point (3, -1) rounded to the nearest tenth?
6.7 units
2.4 units
5.5 units
11.2 units
Bethany is working her way through school. She works two part-time jobs for a total of 30 hours a week. Job A pays $5.90 per hour, and Job B pays $7.20 per hour. How many hours did she work at each job the week that she made $193.90.
Answer:
13 hours at Job B, and 17 hours at Job A.
Step-by-step explanation:
13×7.20= 93.60
17×5.90=100.30
100.30+93.60= 193.90
Jennifer is saving money to buy a bike. The bike costs $258. She has $125 saved, and each week she adds $19 to her savings.
How long will it take her to save enough money to buy the bike?
It will take her___
weeks to save for the bike.
Answer:
7 weeks
Step-by-step explanation:
Answer:
7 weeks
Step-by-step explanation:
Help me with this one please
whats warmer -3 or -4 degree celcius
Which graph can be used to find the solution to the system of equations below? 2x + y = -4 - 3y = 2x + 12 2 -4-3-2-1 -1 1 2 3 5 2. -5 3-2 1 2 1 2 3
Answer:
F
Step-by-step explanation:
2x+y = -4
put into slope-intercept form: y = -2x - 4
-3y = 2x+12
In slope-intercept form: y = -⅔x - 4
Both equations have a y-intercept of -4. There is only one graph where both lines pass through (0,-4).
The solution of the given system of equation is (0, -4). Therefore, option A is the correct answer.
The given system of equations are 2x+y=-4 and -3y=2x+12.
What is a linear system of equations?A system of linear equations consists of two or more equations made up of two or more variables such that all equations in the system are considered simultaneously. The solution to a system of linear equations in two variables is any ordered pair that satisfies each equation independently.
The system of equations can be solved as follows:
Here, 2x+y=-4 ----------(1)
-3y=2x+12 ----------(2)
From equation(1), y=-4-2x
Now, put y=-4-2x in equation (2) and simplify
That is, -3(-4-2x)=2x+12
⇒ 12+6x=2x+12
⇒ 4x=0
⇒ x=0
Substitute x=0 in equation (2), we get
-3y=12
⇒ y=-4
The solution of the given system of equation is (0, -4). Therefore, option A is the correct answer.
To learn more about the linear system of an equations visit:
https://brainly.com/question/27664510.
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a person walks 1/3 mile in 1/24 hour what is the persons speed in miles per hour?
Answer:
8mph
Step-by-step explanation:
Distance= 1/3 mile
time= 1/24 hour
Speed= distance/time
speed = 1/3 divided by 1/24
= 8mph
Answer:
8 im pretty sure
Step-by-step explanation:
Can u help me please
Im pretty sure its D
Answer:
The answer is D
Step-by-step explanation:
Plsss help I suck at math and I’m sure one of you are super smart ♀️
Answer:
3
Step-by-step explanation:
-14x - 7 + 5y - x = -14x - x - 7 + 5y
= -15x - 7 + 5y
Answer:
Step-by-step explanation:
3
The ratio of boys to girls in Mr. Lee's Geography class is 3 to 5. If there are a total of 32 students in the class, how many of them are girls?
What are the values of x and y
E 10 12
x=18*5)14. x=40/4. x=10. y=(15*4)/5 y=60/5 y=12.
resposta : 10 e 12
the diameter of a circle is 19 meters complete the description of how you would find the circumference
Answer:
Then substitute 3.14 for pi and 19 for the diameter.
The image shows the circumference formula.
19/2=9.5
C = 2(9.5)times pi.
C = 19 times 3.14
3.14 times 19 ≈ 59.69
PLEASE HELP ;-; Ill GIVE BRAINLY
What is the solution to the following system of equations? Explain how you know.
Answer:
-3,1
Step-by-step explanation:
When you are doing Systems Of Equations using a graph, the point where the lines intersect is your answer
The scatter plot shows the test scores of a group of students who studied for different amounts of time in a week. A graph shows Hours Spent Studying on x axis and Test Score on y axis .The graph is shown with scale along x axis from 0 to 10 at increments of 1 and scale along y axis from 0 to 100 at increments of 10. The ordered pairs 0, 21 and 0.8, 32 and 1.2,35 and 1.5,39 and 2.1, 42 and 2.3,45 and 2.5,49 and 2.7, 50 and 3, 67 and 4.6, 56 and 5, 69 and 5.3,70 and 5.7,74 and 6.4,78 and 7.2,80 and 7.5,84 and 8.5,88 and 8.7,92 and 9.5,96 are shown on the graph. What will most likely happen to the test scores of students if the number of hours they study increases? Test scores will increase because the graph shows a negative association. Test scores will increase because the graph shows a positive association. Test scores will decrease because the graph shows a positive association. Test scores will decrease because the graph shows a negative association.
Answer:
Test scores will increase because the graph shows a positive association.
Step-by-step explanation:
Since it is going upwards to the right instead of going downwards and for the people who steady more hours they get better scores on there test.
btw i just took it and got it right
From given scatter plot, if the number of hours they study increases then the test scores will increase because the graph shows a positive association.
What is scatter plot?"A type of data representation that shows the relationship between two numerical variables. "
What is positive association?"When the values of one variable tend to increase as the values of the other variable increase, then two variable have positive association."
What is negative association?"When the values of one variable tend to decrease as the values of the other variable increase, then two variable have negative association."
For given question,
The scatter plot shows the test scores of a group of students who studied for different amounts of time in a week.
A scatter plot shows Hours Spent Studying on x axis and Test Score on y axis .
Also we have been given the ordered pairs
(0, 21), (0.8, 32), (1.2, 35), (1.5, 39), (2.1, 42), (2.3, 45) and (2.5, 49) and (2.7, 50) and (3, 67) and (4.6, 56) and (5, 69) and (5.3, 70) and (5.7, 74) and (6.4, 78) and (7.2, 80) and (7.5, 84) and (8.5, 88) and (8.7, 92) and (9.5, 96)
From the given data points of scatter plot,
as x - value increases, y - value also increases.
This means, if the number of hours they study increases, the test scores will increase.
Here, the values of one variable tend to increase as the values of the other variable increase.
This means, there is positive association in variables Hours Spent Studying and Test Scores.
Therefore, from given scatter plot, if the number of hours they study increases then the test scores will increase because the graph shows a positive association.
Learn more about the positive association here:
https://brainly.com/question/858660
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Use the substitution method to solve the system of equations. choose the correct ordered pair.x+y=12 -x=-y+10
Answer:
x=1 y=11
Step-by-step explanation:
What’s the right answer ?
Answer:
B
Step-by-step explanation:
the answer is in the attachment
Hurry pls
10pts
Tell whether the slope of the line
Answer: negative A.
Step-by-step explanation:
the slope of the line is going down so its negative. hope it helps!
Ill mark brainliest please answer!
Answer:
Step-by-step explanation:
You can change radicals to fractional exponents and vice versa. The 1/2 power means square root. The 1/3 power means the cubed root. etc etc
A:) [tex](81)^\frac{1}{2} =\sqrt{81} =9[/tex]
B:) [tex](125)^\frac{1}{3} =\sqrt[3]{125} =5[/tex]
C:) [tex](49)^\frac{3}{2}=\sqrt{(49)^3} =343[/tex]
D:) [tex](8)^\frac{5}{3}=\sqrt[3]{(8)^5}=32[/tex]
A Cepheid variable star is a star whose brightness alternately increases and decreases. Suppose that Cephei Joe is a star for which the interval between times of maximum brightness is 6 days. Its average brightness is 3.5 and the brightness changes by /-0.25. Using this data, we can construct a mathematical model for the brightness of Cephei Joe at time t, where t is measured in days: B(t)=4.2 +0.45sin(2pit/4.4)
A) Find the rate of change of the brightness after t days.
B) Find the rate of increase after one day.
Answer:
a) The rate of change of the brightness after t days is [tex]B^{\prime}(t) = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
b) The rate of increase after one day is of 0.0915.
Step-by-step explanation:
The brightness after t days is given by:
[tex]B(t) = 4.2 + 0.45\sin{(\frac{2\pi t}{4.4})} = 4.2 + 0.45\sin{(0.4545\pi t)}[/tex]
A) Find the rate of change of the brightness after t days.
This is [tex]B^{\prime}(t)[/tex]
The derivative of a constant is 0, the derivative of [tex]\sin{at}[/tex] is [tex]a\cos{at}[/tex]
So, in this case, we have that:
[tex]B^{\prime}(t) = 0.45*0.4545\pi\cos{(0.4545\pi t)} = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
The rate of change of the brightness after t days is [tex]B^{\prime}(t) = 0.204525\pi\cos{(0.4545\pi t)}[/tex]
B) Find the rate of increase after one day.
This is [tex]B^{\prime}(1)[/tex]. So
[tex]B^{\prime}(1) = 0.204525\pi\cos{(0.4545\pi)} = 0.0915[/tex]
The rate of increase after one day is of 0.0915.
9/4 divided by 3/4 =
What is 7 written as a percent? A. 7.2% B. 27% C. 72% D. 720%
what is the simplifed form of the fraction below?
24/30
Answer:
it is 4/5 because you have to divide by 6
homework 1 relations domain range and functions 3-8
Answer:
Step-by-step explanation:
Domain - Set of x-values
Range - Set of y-values
3). Since, x values vary from x = -6 to x = 5,
Domain of the graph = [-6, 5]
Since, y-values vary from y = -2 to y = 3
Range of the graph = [-2, 3]
4). Domain of the graph = [-3, 3]
Range of the graph = [-6, 5]
5). Domain of the graph = (-∞, ∞)
Range of the graph = (-∞, ∞)
6). Domain of the graph = (-∞, 4]
Range of the graph = (-∞, ∞)
7). Domain of the graph = (-∞, ∞)
Range of the graph = [-1, 5]
8) Domain of the graph = [-1, 5)
Range of the graph = [-3, 3)
Answer:
Step-by-step explanation:
Can someone help me im having a hard time
How do I decompose the fraction 4 2/5
Answer:
910293012
Step-by-step explanation:
it is nine thousand four billion atoms in one partial.