This is one single number slightly over 17 thousand.
You may need to erase the comma when typing the answer in.
=========================================================
Explanation:
Let's say that another person steps in for Joe, Susan, John, and Meredith. I'll refer to this person as the teacher (perhaps these 9 friends are students on a field trip).
The 9 friends drops to 9-4 = 5 people when those four named people leave the group temporarily. Then it bumps up to 5+1 = 6 people when the teacher steps in. Wherever the teacher is located, the four friends that left will replace the teacher. This guarantees that those four friends stick together.
There are 6! = 6*5*4*3*2*1 = 720 ways to arrange those 6 people. The exclamation mark is a factorial symbol.
Within any of those 720 permutations, we have 4! = 4*3*2*1 = 24 ways to arrange those group of named people when they come back to replace the teacher.
So overall the answer is 4!*6! = 24*720 = 17,280
You may need to erase the comma when typing the answer in.
-------------
Side note: There are 9! = 362,880 ways to arrange all nine friends regardless if those four mentioned people stick together or not. We see that they stick together roughly (17,280)/(362,880) = 0.0476 = 4.76% of the time.
Which of the following is equivalent to the expression log2a=r? 2a = r logr2 = a 2r = a log2r = a
9514 1404 393
Answer:
(c) 2^r = a
Step-by-step explanation:
The relationship between log forms and exponential forms is ...
[tex]\log_2(a)=r\ \Leftrightarrow\ 2^r=a[/tex]
__
Additional comment
I find this easier to remember if I think of a logarithm as being an exponent.
Here, the log is r, so that is the exponent of the base, 2.
This equivalence can also help you remember that the rules of logarithms are very similar to the rules of exponents.
Answer: Choice C) [tex]2^r = a[/tex]
This is the same as writing 2^r = a
==========================================================
Explanation:
Assuming that '2' is the base of the log, then we'd go from [tex]\log_2(a) = r[/tex] to [tex]2^r = a[/tex]
In either equation, the 2 is a base of some kind. It's the base of the log and it's the base of the exponent.
The purpose of logs is to invert exponential operations and help isolate the exponent. A useful phrase to help remember this may be: "if the exponent is in the trees, then we need to log it down".
The general rule is that [tex]\log_b(y) = x[/tex] converts to [tex]y = b^x[/tex] and vice versa.
I need help solving this problem .
Step-by-step explanation:
here is the answer to your question
Square Footage Frequency
0-499 5
500-999 17
1000-1499 36
1500-1999 115
2000-2499 125
2500-2999 81
3000-3499 47
3500-3999 45
4000-4499 22
4500-4999 7
The accompanying frequency distribution represents the square footage of a random sample of 500 houses that are owner occupied year round. Approximate the mean and standard deviation square footage.
Answer:
2424.5
904.16
Step-by-step explanation:
the mean = ∑frequency /n
∑f = 5+17+36+115+125+81+47+45+22+7 = 500
∑xf = 1212250
∑x²f = 3347037625
sample mean = 1212250/500
= 2424.5
variance = 1/500-1[3347037625 - 1212250²]
= 815710.02
standard deviation is = √variance
standard deviation = √815710.02
= 904.16
help i’ll give brainliest
Answer:
c c c c c c c c c c c c c c c c c c c c
In the accompanying diagram of isosceles triangle ABC, overline AB cong overline BC , BAC =X , and m angle ABC=3x+70
Answer:
x = 22
Step-by-step explanation:
In order to solve this, we need to understand that in an isosceles triangle the two angles that are located at its base are equal to each other.
base - (the side that is not one of the two sides that are equivalent to each other)
Knowing this we can see that ∠ACB will equal ∠BAC, therefore ∠ACB will be equal to x°. Since the sum of all inner angles of a triangle is equal to 180°, we can make the following equation...
x° + x° + (3x + 70)° = 180°
2x° + 3x° + 70° = 180°
5x° = 180° - 70°
5x° = 110°
x° = 110° / 5
x° = 22°
x = 22
Therefore, x = 22.
You and a friend were invited to a
party. You both were asked to bring
pizzas and chips. Your friend brought
three pizzas and four bags of chips
and spent $48.05. You brought five
pizzas and two bags of chips and
spent $67.25. What is the cost of
each? Answer should be in (Pizza, Chips)
Answer:
Pizza = 12.35
Chips = 2.75
Step-by-step explanation:
Let :
Pizza = x
chips = y
3x + 4y = 48.05 - - - (1)
5x + 2y = 67.25 - - - (2)
Multiply (1) by 5 and (2) by 3
15x + 20y = 240.25
15x + 6y = 201.75
Subtract :
20y - 6y = 240.25 - 201.75
14y = 38.50
y = 38.50/ 14
y = 2.75
Put y = 2.75 in (1)
3x + 4(2.75) = 48.05
3x + 11 = 48.05
3x = 48.05 - 11
3x = 37.05
x = 37.05 / 3
x = 12.35
Pizza = 12.35
Chips = 2.75
The thickness X of aluminum sheets is distributed according to the probability density function f(x) = 450 (x2 - x) if 6 < x < 12 0 otherwise 5-1 Derive the cumulative distribution function F(x) for 6 < x < 12. The answer is a function of x and is NOT 1! Show the antiderivative in your solution. 5-2 What is E(X) = {the mean of all sheet thicknesses)? Show the antiderivative in your solution.
Solution :
Given :
[tex]f(x) = \left\{\begin{matrix}\frac{1}{450}(x^2-x) & \text{if } 6 < x < 12 \\ 0 & \text{otherwise}\end{matrix}\right.[/tex]
1. Cumulative distribution function
[tex]$P(X \leq x) = \int_{- \infty}^x f(x) \ dx$[/tex]
[tex]$=\int_{- \infty}^6 f(x) dx + \int_{6}^x f(x) dx $[/tex]
[tex]$=0+\int_6^x \frac{1}{450}(x^2-x) \ dx$[/tex]
[tex]$=\frac{1}{450} \int_6^x (x^2-x) \ dx$[/tex]
[tex]$=\frac{1}{450}\left[\frac{x^3}{3}-\frac{x^2}{2}\right]_6^x$[/tex]
[tex]$=\frac{1}{450}\left[ \left( \frac{x^3}{3} - \frac{x^2}{2}\left) - \left( \frac{6^3}{3} - \frac{6^2}{2} \right) \right] $[/tex]
[tex]$=\frac{1}{450}\left[\frac{x^3}{3} - \frac{x^2}{2} - 54 \right]$[/tex]
2. Mean [tex]$E(x) = \int_{- \infty}^{\infty} \ x \ f(x) \ dx$[/tex]
[tex]$=\int_{6}^{12}x . \left( \frac{1}{450} \ (x^2-x)\right)\ dx$[/tex]
[tex]$=\frac{1}{450} \int_6^{12} \ (x^3 - x^2) \ dx$[/tex]
[tex]$=\frac{1}{450} \left[\frac{x^4}{4} - \frac{x^3}{3} \right]_6^{12} \ dx$[/tex]
[tex]$=\frac{1}{450} \left[ \left(\frac{(12)^4}{4} - \frac{(12)^3}{3} \right) - \left(\frac{(6)^4}{4} - \frac{(6)^3}{3} \right) $[/tex]
[tex]$=\frac{1}{450} [4608 - 252]$[/tex]
= 17.2857
Evaluate the given expression for x=7.
8x +9
The answer is ---
Answer:
The answer is 65
Step-by-step explanation:
Evaluate:
8x + 9
When x = 7
Use PEMDAS order of operations:
8x + 9
= 8(7) + 9
= 56 + 9
= 65
Hope this helps
(-3).(+9)-(-24)-(+6).(+2)
2. About 40 millions of aluminum cans can be recycled each month in the US. A quarter of these aluminum cans are used to make one aluminum boat. How many aluminum boats can be made in one year in the US?
Answer:
48
Step-by-step explanation:
About 40 millions of aluminum cans can be recycled each month in the US. A quarter of these aluminum cans are used to make one aluminum boat. How many aluminum boats can be made in one year in the US?
Given that:
Approximate Number of cans that can be recycled per month in the US = 40 million
Fraction of recycled cans that can be used to make an aluminum boat = 1/4
The number of aluminum boats that can be made in the US in one year :
If about 40 million cans are recycle per month :
The number of boat that can be made from each monthly recycled aluminum cans will be :
Number of monthly recycled can needed to make one boat:
1/4 * 40 million = 10 million cans
Hence, 40,000,000 / 10,000,000 = 4
4 aluminum boats can be made in one month :
Number of months in a year = 12
Number of aluminum boats that can be made in a year :
4 per month * 12 = 48 aluminum boats
A multiple regression model is ^Y = 8.114 + 2.005X1 + 0.774X2. Which of the following values is the estimate for the intercept parameter?
a. 0.774.
b. 8.114.
c. 1.000.
d. 2.005.
Answer:
B. 8.114
Step-by-step explanation:
The intercept parameter is the zero-grade component of the multilinear equation, that is, the component independent from [tex]x_{1}[/tex] and [tex]x_{2}[/tex]. Hence, the intercept parameter of the multilinear regression is 8.114. (Correct answer: B)
Find the perimeter of the
polygon if ZB = D.
3 om
B
4 cm
D
5 cm
C
P = [?] cm
Answer:
16 cm
Step-by-step explanation:
4 + 4 + 3 + 5 = 16
The = sign means that B (which is 4 cm) is equal to D (which had no number)
And because it says that B = D (with the squiggly line (or a tilde)) And the L's (which means that the letters represent an angle) All you have to do is add the numbers together, and you get 16.
Sorry if I explained it badly, you at least got the answer.
(And also, if I'm wrong, please tell me.)
Answer:
P = 32 cm
Step-by-step explanation:
Im just putting the right answer up so you don't accidentally put in the wrong one.
PLEASE HELPPPP WILL GIVE BRAINLIESTTTT
Factor the following expressions completely. Show and check all work on your own paper.
9x2-18x+9
Hi there!
[tex]\large\boxed{9(x - 1)^{2}}[/tex]
9x² - 18x + 9
We can begin by factoring out a 9 from each term:
9(x² - 2x + 1)
Now, find two terms that add up to -2 and equal 1 when multiplied. We get:
9(x - 1)(x - 1)
Or:
9(x - 1)²
Cole biked at 5 mph for 1 hours. Which of the following choices show how far he biked?
A=5.5 miles
B=6.5 miles
C=7.5 miles
D=10 miles
Answer:
Most Likely A, 5.5 Miles
Step-by-step explanation:
However the question doesn't make sense as the logical answer is simply 5 miles, but the safest choice is 5.5
The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft. A rock formation rises to a peak 171 ft above the ocean floor. How many feet below the top of the rock formation is the diver?
Answer:
The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft.
Step-by-step explanation:
A point is selected at random from a line segment of length l, dividing it into two line segments. What is the probability that the longer line segment is at least three times as long as the shorter segment
Answer:
3/4
Step-by-step explanation:
Let a be the length of the shorter line segment and b be the length of the longer line segment.
Since the length of the line segment is l, we have that the length of the line segment equals length of shorter line segment + length of longer line segment.
So, l = a + b
Since we require that the longer line segment be at least three times longer than the shorter line segment, we have that b = 3a
So, l = a + b
l = a + 3a
l = 4a
The probability that the shorter line segment will be a(or 3 times shorter than b) is P(a) = length of shorter line segment/length of line segment = a/l
Since l = 4a.
a/l = 1/4
So, P(a) = 1/4
The probability that a will be less than 3 times shorter that b is P(a ≤ 1) = P(0) + P(a) = 0 + 1/4 = 1/4
The probability that b will be 3 times or more greater than a is thus P(b ≥ 3) = 1 - P(a ≤ 1) = 1 - 1/4 = 3/4
A bricklayer needs to order 6 300 kg of building sand.
a) Write 6 300 kg in grams, giving your answer in standard form.
One grain of this sand approximately weighs 7 x 10°g.
b) How many grains of sand are there in 6 300 kg of sand? Give your answer in standard from.
Answer:
It would be 6300000. I can't write this in standard form.
Step-by-step explanation:
Answer:
6.3 x 10^6
Step-by-step explanation:
What is the equation of a parabola with its vertex at the origin and its focus at (–2, 0)?
Step-by-step explanation:
this is the answerI hope it helps
A loan of £1000 has a compound interest rate of 2.7% charged monthly. Express the original loan as a percentage of the total amount awed after 2 months if no payment are made
Answer:
£1054.729
Step-by-step explanation:
To find compound interest you need to use the equation 1000(1.027)^x.
To find the interest rate (1.027):
100 + 2.7 = 102.7
102.7 / 100 = 1.027
The value of x is the amount of months if no payment is made in this situation, so 2 would be the x value for this problem.
Hope this helps!
A radioactive substance decays exponentially: The mass at time t is m(t) = m(0)e^kt, where m(0) is the initial mass and k is a negative constant. The mean life M of an atom in the substance is
[infinity]
M = âk â« te^kt dt.
0
For the radioactive carbon isotope, 14C, used in radiocarbon dating, the value of k is -0.000121. Find the mean life of a 14C atom.
Answer:
mean life = 8264.5 s
Step-by-step explanation:
k = - 0.000121
The relation is given by
[tex]m = mo e^{kt}[/tex]
Now, the mean life is the life time for which the sample retains.
The mean life is the reciprocal of the decay constant.
The relation between the mean life and the decay constant is
[tex]\tau =\frac{1}{k}\\\\\tau = \frac{1}{0.000121} = 8264.5 seconds[/tex]
What are the solutions to the system of equations graphed below?
Answer:
D
Step-by-step explanation:
solution is the points where the two graphs intersect.
they intersect at (-3,-3) and (0,6)
Would you kindly help me.Im having a hard time understanding and I've been crying a lot trying to understand it
Yess again pls help!
Tyyy
Two balls are drawn with replacement from a bag containing 12 red,3 white and 1 blue balls.what is the probability that both are red?
The probability that both the balls are red = [tex]\bold{\frac{11}{20}}[/tex]
What is probability?"Probability is a branch of mathematics which deals with finding out the likelihood of the occurrence of an event."
Formula of the probability of an event A is:P(A) = n(A)/n(S)
where, n(A) is the number of favorable outcomes, n(S) is the total number of events in the sample space.
What is the formula of combination?"[tex]^nC_r=\frac{n!}{r!(n-r)!}[/tex]"
For given question,
a bag contains 12 red, 3 white and 1 blue balls.
Total balls = 12 + 3 + 1
Total = 16
Two balls are drawn from a bag.
The number of possible ways of drawing 2 balls from the bag are:
Using combination formula,
[tex]^{16}C_2\\\\=\frac{16!}{2!(16-2)!}\\\\ =\frac{16!}{2!\times 12!}\\\\ =120[/tex]
So, n(S) = 120
Two balls are drawn with replacement from a bag.
We need to find the probability that both are red.
Let event A: both the balls are red
[tex]\Rightarrow n(A)=^{12}C_2[/tex]
Using combination formula,
[tex]^{12}C_2\\\\=\frac{12!}{2!\times (12-2)!}\\\\= \frac{12!}{2!\times 10!}\\\\ =66[/tex]
Using probability formula,
[tex]\Rightarrow P(A)=\frac{n(A)}{n(S)}\\\\\Rightarrow P(A)=\frac{66}{120}\\\\\Rightarrow P(A)=\frac{11}{20}[/tex]
Therefore, the probability that both the balls are red = [tex]\bold{\frac{11}{20}}[/tex]
Learn more about probability here:
brainly.com/question/11234923
#SPJ2
I feel like it would be 6/10 but that’s not an answer
Answer:
I think it would be 3/4
Step-by-step explanation:
Which division problem does the diagram below best illustrate?
A diagram with 8 ovals containing 4 squares each.
O 16 divided by 4 = 4
O 32 divided by 4 = 8
O 36 divided by 4 = 9
O 8 divided by 2 = 4
Answer:
The answer is 32 divided by 4
Step-by-step explanation:
Because in each box there is 4. There are 8 ovals all together. So 8×4, you get 32 and divide it by the number of squares in an oval which is 4
Answer:
the answer is 32 divided by 4=8
Step-by-step explanation:
because when you look at the ovals there's eight ovals and in side there's four squares..
HOPE THIS HELPS!!!!!
1. Suppose half of all newborns are girls and half are boys. Hospital A, a large city hospital, records an average of 50 births a day. Hospital B, a small, rural hospital, records an average of 10 births a day. On a particular day, which hospital is less likely to record 80% or more female births?
Answer:
5%
Step-by-step explanation:
Hospital A (with 50 births a day), because the more births you see, the closer the proportions will be to 0.5.
Hospital B (with 10 births a day), because with fewer births there will be less variability.
The two hospitals are equally likely to record such an event, because the probability of a boy does not depend on the number of births
Two hospitals have an equal chance of recording such an event.
What is probability?The area of mathematics known as probability deals with numerical representations of the likelihood that an event will occur or that a statement is true. An event's probability is a number between 0 and 1, where, roughly speaking, 0 denotes the event's impossibility and 1 denotes certainty.
Given
Hospital A (with 50 births per day), as the proportions will be closer to 0.5 the more births you see.
Hospital B (with 10 births per day), thus there will be less unpredictability with fewer births.
Due to the fact that the likelihood of a boy does not rely on the number of births, the two hospitals have an equal chance of recording such an event.
To learn more about probability refer to:
https://brainly.com/question/13604758
#SPJ2
Levi makes the minimum salary for actuary. Andres maybe the median salary for cpa. Who makes more money
Answer:
Andres
why?
Because he is median salary for cpa
Write an equation that expresses the following relationship.
d varies directly with w and inversely with p.
In your equation, use k as the constant of proportionality.
9514 1404 393
Answer:
d = kw/p
Step-by-step explanation:
When d varies directly with w, the equation is ...
d = kw
When d varies inversely with p, the equation is ...
d = k/p
When d does both, the equation is ...
d = kw/p
1. You measure 24 textbooks' weights, and find they have a mean weight of 75 ounces. Assume the population standard deviation is 3.3 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight.
2. You measure 37 backpacks' weights, and find they have a mean weight of 45 ounces. Assume the population standard deviation is 10.1 ounces. Based on this, construct a 95% confidence interval for the true population mean backpack weight.
3. You measure 30 watermelons' weights, and find they have a mean weight of 37 ounces. Assume the population standard deviation is 4.1 ounces. Based on this, what is the maximal margin of error associated with a 90% confidence interval for the true population mean watermelon weight.
4. A student was asked to find a 99% confidence interval for widget width using data from a random sample of size n = 16. Which of the following is a correct interpretation of the interval 11.8 < μ < 20.4?
A. There is a 99% chance that the mean of a sample of 16 widgets will be between 11.8 and 20.4.
B. The mean width of all widgets is between 11.8 and 20.4, 99% of the time. We know this is true because the mean of our sample is between 11.8 and 20.4.
C. With 99% confidence, the mean width of all widgets is between 11.8 and 20.4.
D. With 99% confidence, the mean width of a randomly selected widget will be between 11.8 and 20.4.
E. There is a 99% chance that the mean of the population is between 11.8 and 20.4.
5. For a confidence level of 90% with a sample size of 23, find the critical t value.
Answer:
(73.845 ; 76.155) ;
(41.633 ; 48.367) ;
1.273 ;
C. With 99% confidence, the mean width of all widgets is between 11.8 and 20.4. ;
1.717
Step-by-step explanation:
1.)
Given :
Mean, xbar = 75
Sample size, n = 24
Sample standard deviation, s = 3.3
α = 90%
Confidence interval = mean ± margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 90% ; df = 24 - 1 = 23
Tcritical = 1.714
Margin of Error = 1.714 * 3.3/√24 = 1.155
Confidence interval = 75 ± 1.155
Confidence interval = (73.845 ; 76.155)
2.)
Given :
Mean, xbar = 45
Sample size, n = 37
Sample standard deviation, s = 10.1
α = 95%
Confidence interval = mean ± margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 95% ; df = 37 - 1 = 36
Tcritical = 2.028
Margin of Error = 2.028 * 10.1/√37 = 3.367
Confidence interval = 45 ± 3.367
Confidence interval = (41.633 ; 48.367)
3.)
Given :
Mean, xbar = 37
Sample size, n = 30
Sample standard deviation, s = 4.1
α = 90%
Margin of Error = Tcritical * s/√n
Tcritical at 90% ; df = 30 - 1 = 29
Tcritical = 1.700
Margin of Error = 1.700 * 4.1/√30 = 1.273
5.)
Sample size, n = 23
Confidence level, = 90%
df = n - 1 ; 23 - 1 = 22
Tcritical(0.05, 22) = 1.717