Answer:
Unit rate = 81 riders/ car.
Step-by-step explanation:
Given
729 riders in 9 cars
we have to find unit rate in terms of riders per car
let the the riders per car (i.e rate) be x.
If there are 9 cars then
total no. of riders in 9 cars = no. of cars * riders per car = 9*x = 9x
given that 729 riders in 9 cars
then
9x = 729
=> x = 729/9 = 81
Thus, riders per car = x = 81.
Unit rate is 81 riders per car.
For what values (cases) of the variables the expression does not exist: a / a−b
Answer:
a=b
Step-by-step explanation:
When the denominator is zero, the expression is undefined
a-b=0
a=b
To reach a particular department at a warehouse, a caller must dial a 4-digit extension. Suppose a caller remembers that the first and last digits of an extension are 5, but they are not sure about the other digits.
How many possible extensions might they have to try?
Answer:
100 possible extensions
Step-by-step explanation:
we can calculated how many possible extensions they have to try using the rule of multiplication as:
___1_____*___10_____*___10_____*____1____ = 100
1st digit 2nd digit 3rd digit 4th digit
You know that the 1st and 4th digits of the extension are 5. it means that you just have 1 option for these places. On the other hand, you don't remember nothing about the 2nd and 3rd digit, it means that there are 10 possibles digits (from 0 to 9) for each digit.
So, There are 100 possibles extensions in which the 5 is the first and last digit.
Find the area of the largest rectangle that can be inscribed in a right triangle with legs of lengths 4 cm and 6 cm if two sides of the rectangle lie along the legs. webassign cengage
Answer:
[tex]6cm^2[/tex]
Step-by-step explanation:
Let x and y be the sides of the rectangle.
Area of the Triangle, A(x,y)=xy
From the diagram, Triangle ABC is similar to Triangle AKL
AK=4-y
Therefore:
[tex]\dfrac{x}{6} =\dfrac{4-y}{4}[/tex]
[tex]4x=6(4-y)\\x=\dfrac{6(4-y)}{4} \\x=1.5(4-y)\\x=6-1.5y[/tex]
We substitute x into A(x,y)
[tex]A=y(6-1.5y)=6y-1.5y^2[/tex]
We are required to find the maximum area. This is done by finding
the derivative of Aand solving for the critical points.
Derivative of A:
[tex]A'(y)=6-3y\\$Set $A'=0\\6-3y=0\\3y=6\\y=2$ cm[/tex]
Recall that: x=6-1.5y
x=6-1.5(2)
x=6-3
x=3cm
Therefore, the maximum rectangle area is:
Area =3 X 2 =[tex]6cm^2[/tex]
Sue works an average of 45 hours each week. She gets paid $10.12 per hour and time-and-a-half for all hours over 40 hours per week. What is her annual income?
Step-by-step explanation:
40 x $10.12/hr = $404.80
5 x $15.18/hr = $ 75.90
over time = $10.12 + $5.06 ( half of $10.12) = $15.18/hr
$404.80 + $75.90 = $480.70/weekly pay
assuming she works 52 weeks a year
$480.70 × 52 weeks = $24,996.40/yr
The volume of a water in a fish tank is 84,000cm the fish tank has the length 60cm and the width 35cm. The water comes to 10cm from the top of the tank. calculate the height of the tank.
Answer:
Height of tank = 50cm
Step-by-step explanation:
Volume of water from tank that the water is 10cm down is 84000cm³
Length = 60cm
Width = 35cm
Height of water = x
Volume = length* width* height
Volume= 84000cm³
84000 = 60*35*x
84000= 2100x
84000/2100= x
40 = x
Height of water= 40cm
Height of tank I = height of water+ 10cm
Height of tank= 40+10= 50cm
Height of tank = 50cm
Which expression is equivalent to 24 ⋅ 2−7?
Answer:
41
Step-by-step explanation:
[tex]24*2-7=\\48-7=\\41[/tex]
I really need help, please help me.
Answer:
96 degrees
Step-by-step explanation:
Since x is half of 168, its angle measure is 84 degrees. Since x and y are a linear pair, their angle measures must add to 180 degrees, meaning that:
y+84=180
y=180-84=96
Hope this helps!
The area of the sector of a circle with a radius of 8 centimeters is 125.6 square centimeters. The estimated value of is 3.14.
The measure of the angle of the sector is
Answer:
225º or 3.926991 radians
Step-by-step explanation:
The area of the complete circle would be π×radius²: 3.14×8²=200.96
The fraction of the circle that is still left will be a direct ratio of the angle of the sector of the circle.
[tex]\frac{125.6}{200.96}[/tex]=.625. This is the ratio of the circe that is in the sector. In order to find the measure we must multiply it by either the number of degrees in the circle or by the number of radians in the circle (depending on the form in which you want your answer).
There are 360º in a circle, so .625×360=225 meaning that the measure of the angle of the sector is 225º.
We can do the same thing for radians, if necessary. There are 2π radians in a circle, so .625×2π=3.926991 radians.
Answer:
225º
Step-by-step explanation:
A sample of 8 students was asked how often they used campus dining facilities during the past month. The responses were as follows. 4 1 6 1 2 10 2 6 The sample standard deviation is _____.
Answer:
Your answer is 3.16227766
Step-by-step explanation:
1. A door of a lecture hall is in a parabolic shape. The door is 56 inches across at the bottom of the door and parallel to the floor and 32 inches high. Sketch and find the equation describing the shape of the door. If you are 22 inches tall, how far must you stand from the edge of the door to keep from hitting your head
Answer:
See below in bold.
Step-by-step explanation:
We can write the equation as
y = a(x - 28)(x + 28) as -28 and 28 ( +/- 1/2 * 56) are the zeros of the equation
y has coordinates (0, 32) at the top of the parabola so
32 = a(0 - 28)(0 + 28)
32 = a * (-28*28)
32 = -784 a
a = 32 / -784
a = -0.04082
So the equation is y = -0.04082(x - 28)(x + 28)
y = -0.04082x^2 + 32
The second part is found by first finding the value of x corresponding to y = 22
22 = -0.04082x^2 + 32
-0.04082x^2 = -10
x^2 = 245
x = 15.7 inches.
This is the distance from the centre of the door:
The distance from the edge = 28 - 15.7
= 12,3 inches.
Find sin angle ∠ C.
A. 12/13
B. 1
C. 13/12
D. 13/5
Answer:
A
Step-by-step explanation:
We can use the trigonometric ratios. Recall that sine is the ratio of the opposite side to the hypotenuse:
[tex]\displaystyle \sin(C)=\frac{\text{opposite}}{\text{hypotenuse}}[/tex]
The opposite side with respect to ∠C is 24 and the hypotenuse is 26.
Hence:
[tex]\displaystyle \sin(C)=\frac{24}{26}=\frac{12}{13}[/tex]
Our answer is A.
During the period of time that a local university takes phone-in registrations, calls come in at the rate of one every two minutes.a. What is the expected number of calls in one hour?b. What is the probability of three calls in five minutes?c. What is the probability of no calls in a five-minute period?
Answer:
Step-by-step explanation:
This is a poisson distribution. Let x be a random representing the number of calls in a given time interval.
a) the expected number of calls in one hour is the same as the mean score in 60 minutes. Thus,
Mean score = 60/2 = 30 calls
b) The interval of interest is 5 minutes.
µ = 5/2 = 2.5
We want to determine P(x = 3)
Using the Poisson probability calculator,
P(x = 3) = 0.21
c) µ = 5/2 = 2.5
We want to determine P(x = 0)
Using the Poisson probability calculator,
P(x = 0) = 0.08
Find the product of
3/5 × 7/11
Answer:
21/55
Step-by-step explanation:
Simply multiply the top 2 together:
3 x 7 = 21
And the bottom 2 together:
5 x 11 = 55
21/55 is your answer!
Overweight participants who lose money when they don’t meet a specific exercise goal meet the goal more often, on average, than those who win money when they meet the goal, even if the final result is the same financially. In particular, participants who lost money met the goal for an average of 45.0 days (out of 100) while those winning money or receiving other incentives met the goal for an average of 33.7 days. The incentive does make a difference. In this exercise, we ask how big the effect is between the two types of incentives. Find a 90% confidence interval for the difference in mean number of days meeting the goal, between people who lose money when they don't meet the goal and those who win money or receive other similar incentives when they do meet the goal. The standard error for the difference in means from a bootstrap distribution is 4.14.
Answer:
The 90% confidence interval for the difference in mean number of days meeting the goal is (4.49, 18.11).
Step-by-step explanation:
The (1 - α)% confidence interval for the difference between two means is:
[tex]CI=\bar x_{1}-\bar x_{2}\pm z_{\alpha/2}\times SE_{\text{diff}}[/tex]
It is provided that:
[tex]\bar x_{1}=45\\\bar x_{2}=33.7\\SE_{\text{diff}} =4.14\\\text{Confidence Level}=90\%[/tex]
The critical value of z for 90% confidence level is,
z = 1.645
*Use a z-table.
Compute the 90% confidence interval for the difference in mean number of days meeting the goal as follows:
[tex]CI=\bar x_{1}-\bar x_{2}\pm z_{\alpha/2}\times SE_{\text{diff}}[/tex]
[tex]=45-33.7\pm 1.645\times 4.14\\\\=11.3\pm 6.8103\\\\=(4.4897, 18.1103)\\\\\approx (4.49, 18.11)[/tex]
Thus, the 90% confidence interval for the difference in mean number of days meeting the goal is (4.49, 18.11).
divide and simplify x^2+7x+12 over x+3 divided by x-1 over x+4
Answer:
[tex]\dfrac{x^2+8x+16}{x-1}[/tex]
Step-by-step explanation:
In general, "over" and "divided by" are used to mean the same thing. Parentheses are helpful when you want to show fractions divided by fractions. Here, we will assume you intend ...
[tex]\dfrac{\left(\dfrac{x^2+7x+12}{x+3}\right)}{\left(\dfrac{x-1}{x+4}\right)}=\dfrac{(x+3)(x+4)}{x+3}\cdot\dfrac{x+4}{x-1}=\dfrac{(x+4)^2}{x-1}\\\\=\boxed{\dfrac{x^2+8x+16}{x-1}}[/tex]
Which are the right ones?
Answer:
20 4/5
Step-by-step explanation:
13/5 times 8/1
104/5
which is simplify
to 20 4/5\
hope this helps
A College Alcohol Study has interviewed random samples of students at four-year colleges. In the most recent study, 494 of 1000 women reported drinking alcohol and 552 of 1000 men reported drinking alcohol. What is the 95% confidence interval of the drinking alcohol percentage difference between women and men
Answer:
The 95% confidence interval for the difference between the proportion of women who drink alcohol and the proportion of men who drink alcohol is (-0.102, -0.014) or (-10.2%, -1.4%).
Step-by-step explanation:
We want to calculate the bounds of a 95% confidence interval of the difference between proportions.
For a 95% CI, the critical value for z is z=1.96.
The sample 1 (women), of size n1=1000 has a proportion of p1=0.494.
[tex]p_1=X_1/n_1=494/1000=0.494[/tex]
The sample 2 (men), of size n2=1000 has a proportion of p2=0.552.
[tex]p_2=X_2/n_2=552/1000=0.552[/tex]
The difference between proportions is (p1-p2)=-0.058.
[tex]p_d=p_1-p_2=0.494-0.552=-0.058[/tex]
The pooled proportion, needed to calculate the standard error, is:
[tex]p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{494+552}{1000+1000}=\dfrac{1046}{2000}=0.523[/tex]
The estimated standard error of the difference between means is computed using the formula:
[tex]s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.523*0.477}{1000}+\dfrac{0.523*0.477}{1000}}\\\\\\s_{p1-p2}=\sqrt{0.000249+0.000249}=\sqrt{0.000499}=0.022[/tex]
Then, the margin of error is:
[tex]MOE=z \cdot s_{p1-p2}=1.96\cdot 0.022=0.0438[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=(p_1-p_2)-z\cdot s_{p1-p2} = -0.058-0.0438=-0.102\\\\UL=(p_1-p_2)+z\cdot s_{p1-p2}= -0.058+0.0438=-0.014[/tex]
The 95% confidence interval for the difference between proportions is (-0.102, -0.014).
Use Green's Theorem to evaluate ?C F·dr. (Check the orientation of the curve before applying the theorem.)
F(x, y) =< x + 4y3, 4x2 + y>
C consists of the arc of the curve y = sin x from (0, 0) to (p, 0) and the line segment from (p, 0) to (0, 0).
Answer:
Step-by-step explanation:
given a field of the form F = (P(x,y),Q(x,y) and a simple closed curve positively oriented, then
[tex]\int_{C} F \cdot dr = \int_A \frac{dQ}{dx} - \frac{dP}{dy} dA[/tex] where A is the area of the region enclosed by C.
In this case, by the description we can assume that C starts at (0,0). Then it goes the point (pi,0) on the path giben by y = sin(x) and then return to (0,0) along the straigth line that connects both points. Note that in this way, the interior the region enclosed by C is always on the right side of the point. This means that the curve is negatively oriented. Consider the path C' given by going from (0,0) to (pi,0) in a straight line and the going from (pi,0) to (0,0) over the curve y = sin(x). This path is positively oriented and we have that
[tex] \int_{C} F\cdot dr = - \int_{C'} F\cdot dr[/tex]
We use the green theorem applied to the path C'. Taking [tex] P = x+4y^3, Q = 4x^2+y[/tex] we get
[tex] \int_{C'} F\cdot dr = \int_{A} 8x-12y^2dA[/tex]
A is the region enclosed by the curves y =sin(x) and the x axis between the points (0,0) and (pi,0). So, we can describe this region as follows
[tex]0\leq x \leq \pi, 0\leq y \leq \sin(x)[/tex]
This gives use the integral
[tex] \int_{A} 8x-12y^2dA = \int_{0}^{\pi}\int_{0}^{\sin(x)} 8x-12y^2 dydx[/tex]
Integrating accordingly, we get that [tex]\int_{C'} F\cdot dr = 8\pi - \frac{16}{3}[/tex]
So
[tex] \int_{C} F cdot dr = - (8\pi - \frac{16}{3}) = \frac{16}{3} - 8\pi [/tex]
The length of time for one individual to be served at a cafeteria is an exponential random variable with mean of 5 minutes. Assume a person has waited for at least 3 minutes to be served. What is the probability that the person will need to wait at least 7 minutes total
Answer:
44.93% probability that the person will need to wait at least 7 minutes total
Step-by-step explanation:
To solve this question, we need to understand the exponential distribution and conditional probability.
Exponential distribution:
The exponential probability distribution, with mean m, is described by the following equation:
[tex]f(x) = \mu e^{-\mu x}[/tex]
In which [tex]\mu = \frac{1}{m}[/tex] is the decay parameter.
The probability that x is lower or equal to a is given by:
[tex]P(X \leq x) = \int\limits^a_0 {f(x)} \, dx[/tex]
Which has the following solution:
[tex]P(X \leq x) = 1 - e^{-\mu x}[/tex]
The probability of finding a value higher than x is:
[tex]P(X > x) = 1 - P(X \leq x) = 1 - (1 - e^{-\mu x}) = e^{-\mu x}[/tex]
Conditional probability:
We use the conditional probability formula to solve this question. It is
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened.
[tex]P(A \cap B)[/tex] is the probability of both A and B happening.
P(A) is the probability of A happening.
The length of time for one individual to be served at a cafeteria is an exponential random variable with mean of 5 minutes
This means that [tex]m = 5, \mu = \frac{1}{5} = 0.2[/tex]
Assume a person has waited for at least 3 minutes to be served. What is the probability that the person will need to wait at least 7 minutes total
Event A: Waits at least 3 minutes.
Event B: Waits at least 7 minutes.
Probability of waiting at least 3 minutes:
[tex]P(A) = P(X > 3) = e^{-0.2*3} = 0.5488[/tex]
Intersection:
The intersection between waiting at least 3 minutes and at least 7 minutes is waiting at least 7 minutes. So
[tex]P(A \cap B) = P(X > 7) = e^{-0.2*7} = 0.2466[/tex]
What is the probability that the person will need to wait at least 7 minutes total
[tex]P(B|A) = \frac{0.2466}{0.5488} = 0.4493[/tex]
44.93% probability that the person will need to wait at least 7 minutes total
(b) How many different groups of children can be chosen from a class of 18 children if the class contains one set of twins who must not be separated?
Jeff's net monthly income is $2550. His monthly expense for rent is $625. What percent of his net monthly income is his rent? (Round your answer to the nearest whole percent.)
Answer:
25%
I cannot really describe how I did it but I am pretty sure it is correct.
Which of the following equations describes the line shown below? Check all
that apply
Answer:
y-7=1/2(x-8)
y-4=1/2(x-2)
Step-by-step explanation:
Slope: 3/6, or 1/2
y-7=1/2(x-8)
y-4=1/2(x-2)
Please answer this correctly
Answer:
Raspberry: 30%
Strawberry: 15%
Apple: 20%
Lemon: 35%
Step-by-step explanation:
18 + 9 + 12 + 21 = 60 (there are 60 gummy worms)
18 out of 60 = 30%
9 out of 60 = 15%
12 out of 60 = 20%
21 out of 60 = 35%
Please mark Brainliest
Hope this helps
Answer:
Raspberry Worms: 30%
Strawberry Worms: 15%
Apple Worms: 20%
Lemon Worms: 35%
Step-by-step explanation:
Raspberry Worms: [tex]\frac{18}{18+9+12+21}=\frac{18}{60}=\frac{30}{100}[/tex] or 30%
Strawberry Worms: [tex]\frac{9}{18+9+12+21}=\frac{9}{60} =\frac{15}{100}[/tex] or 15%
Apple Worms: [tex]\frac{12}{18+9+12+21} =\frac{12}{60} =\frac{20}{100}[/tex] or 20%
Lemon Worms: [tex]\frac{21}{18+9+12+21} =\frac{21}{60} =\frac{35}{100}[/tex] or 35%
What is the value of (4-2) – 3x4?
О-20
оооо
4
Answer:
-10
Step-by-step explanation:
Use the Order of Operations - PEMDAS
Do what is in parentheses first - (4-2) = 2
Next multiply 3 and 4 = 12
Last, perform 2 - 12; which equals -10
Suppose that prices of recently sold homes in one neighborhood have a mean of $225,000 with a standard deviation of $6700. Using Chebyshev's Theorem, what is the minimum percentage of recently sold homes with prices between $211,600 and $238,400
Answer:
[tex] 211600 = 225000 -k*6700[/tex]
[tex] k = \frac{225000-211600}{6700}= 2[/tex]
[tex] 238400 = 225000 +k*6700[/tex]
[tex] k = \frac{238400-225000}{6700}= 2[/tex]
So then the % expected would be:
[tex] 1- \frac{1}{2^2}= 1- 0.25 =0.75[/tex]
So then the answer would be 75%
Step-by-step explanation:
For this case we have the following info given:
[tex] \mu = 225000[/tex] represent the true mean
[tex]\sigma =6700[/tex] represent the true deviation
And for this case we want to find the minimum percentage of sold homes between $211,600 and $238,400.
From the chebysev theorem we know that we have [tex]1 -\frac{1}{k^2}[/tex] % of values within [tex]\mu \pm k\sigma[/tex] if we use this formula and the limit given we have:
[tex] 211600 = 225000 -k*6700[/tex]
[tex] k = \frac{225000-211600}{6700}= 2[/tex]
[tex] 238400 = 225000 +k*6700[/tex]
[tex] k = \frac{238400-225000}{6700}= 2[/tex]
So then the % expected would be:
[tex] 1- \frac{1}{2^2}= 1- 0.25 =0.75[/tex]
So then the answer would be 75%
Circle O has a circumference of 36π cm. Circle O with radius r is shown. What is the length of the radius, r? 6 cm 18 cm 36 cm 72 cm
Answer: 18 cm
Step-by-step explanation:
We know the circumference formula is C=2πr. Since our circumference is given in terms of π, we can easily figure out what the radius is.
36π=2πr [divide both sides by π to cancel out]
36=2r [divide both sides by 2]
r=18 cm
Answer:
18cm
Step-by-step explanation:
because i found it lol
Express 12/16 in quarters
Word related to circle
Answer:
Center, radius, chord, diameter... are Words related to circle
Rocco used these steps to solve the equation 4x + 6 = 4 + 2(2x + 1). Which choice describes the meaning of his result, 6 = 6?
Answer:
infinite solutions
Step-by-step explanation:
it means that all x are solution of this equation as 6=6 is always true
Math 7th grade. help please!!!
Answer:
1 .angle S is 90 degree
2. 12
3. 155 degree
1. x = 3
hope it helps .....