At 7:00 one Summer morning Harry and Hermione hopped into their speedy more motorboat and left Hogwarts dock. They arrived at Dumbledore Wharf 35 minutes later. During the busy summer months a car ferry departs from Dumbledore wharf every five minutes. Tourists crowd onto the ferry for the 55 minute ride to Hogswarts dock. If Harry and Hermione followed the route that the car ferries take, how many car ferries did they see on their trip?
9514 1404 393
Answer:
19
Step-by-step explanation:
If we assume that the car ferries start at or before 6:05, and each 5 minutes thereafter, and if we count the ferries at the dock on either end, the total number seen is the number of ferries encountered in ...
55 +35 = 90 . . . minutes
That is, it is the number already in transit when they leave, plus the number that start while they are traveling.
That's 90/5 +1* = 19 ferries.
_____
The attached diagram can give an idea. Each up-sloping line represents a ferry in-transit. The left side is Dumbledore Wharf; the right side is Hogwarts dock. Each horizontal unit represents the distance traveled by a ferry in 5 minutes. Each vertical unit represents a 5-minute interval.
The down-sloping line represents the motorboat travel. The dots at either end of the latter line represent car ferries that are at the dock, just arriving or just-departing. Altogether, there are 17 places where the lines cross, in addition to the boats at the docks.
__
* the +1 is because the number of points defining intervals is 1 more than the number of intervals.
Researchers investigated whether the proportion of American teenagers with some level of hearing loss was diff erent in 2005–2006 than in 1988–1994. They collected data on random samples of American teenagers in those two time periods. Let the symbol π05-06 denote the population proportion of American teenagers with some level of hearing loss in 2005–2006 and similarly for π88-94. A 95% confidence interval for the parameter π05-06 − π88-94 turns out to be (0.0015, 0.0467).
Required:
What is an appropriate conclusion to draw?
Complete Question
Researchers investigated whether the proportion of American teenagers with some level of hearing loss was different in 2005–2006 than in 1988–1994. They collected data on random samples of American teenagers in those two time periods. Let the symbol [tex]\pi __{05-06}}[/tex] denote the population proportion of American teenagers with some level of hearing loss in 2005–2006 and similarly for [tex]\pi__{{88-94}}[/tex]. A 95% confidence interval for the parameter [tex]\pi__{{05-06}} }- \pi__{{88-94}}[/tex] turns out to be (0.0015, 0.0467).
Required:
What is an appropriate conclusion to draw?
Answer:
The appropriate conclusion is
The sample data provide little evidence to doubt that the proportion of American teenagers with hearing loss was the same in 1988-1994 as in 2005-2006
Step-by-step explanation:
Generally the appropriate conclusion is
The sample data provide little evidence to doubt that the proportion of American teenagers with hearing loss was the same in 1988-1994 as in 2005-2006.
This because the confidence intervals are very close to zero , i.e both the upper limit and the lower limit are close to zero and if we are take 0.05 as our level of significance we see that the both values of the confidence level are small to be significant
Find the general solution of y''' + 9y'' + y' − 111y = 0 if it is known that y1 = e−6x cos(x) is one solution.
Answer:
[tex]\mathbf{y(x) = \dfrac{(c_1 + c_2) \ cos (x)}{e^{6x} }+ \dfrac{i(c_1 -c_2) \ sin (x)}{e^{6x}}+ c_3e^{3\ x}}[/tex]
Step-by-step explanation:
The objective of this question is to solve:
[tex]\dfrac{dy(x)}{dx}+ 9\dfrac{d^2y(dx)}{dx^2}+\dfrac{d^3y(x)}{dx^3}-111y(x) = 0 :[/tex]
Suppose the general solution is proportional to [tex]e^{\lambda x}[/tex] for [tex]\lambda[/tex] is constant; Then:
Let's replace [tex]y(x) = e^{\lambda\ x}[/tex] into the above equation:
i.e.
[tex]\dfrac{d^3}{dx^3}(e ^{\lambda x} )+ 9 \dfrac{d^2}{dx^2}(e ^{\lambda x} ) + \dfrac{d}{dx}(e ^{\lambda x} )- 111 \ e ^{\lambda x} = 0[/tex]
To Replace:
[tex]\dfrac{d^3}{dx^3}(e ^{\lambda x} )[/tex] with [tex]\lambda^3 e ^{\lambda x }[/tex]
[tex]\dfrac{d^2}{dx^2}(e ^{\lambda x} ) \ with \ \lambda^2 e^{\lambda\ x}[/tex]
[tex]\dfrac{d}{dx}(e ^{\lambda x} ) \ with \ \lambda e ^{\lambda \ x}[/tex]
Thus;
[tex]\lambda^3 e ^{\lambda x }[/tex] + [tex]9 \lambda^2 e^{\lambda\ x}[/tex] + [tex]\lambda e ^{\lambda \ x}[/tex] - 111 [tex]e ^{\lambda \ x}[/tex] = 0
[tex]e ^{\lambda \ x} (\lambda ^3 + 9 \lambda ^2 + \lambda - 111 )= 0[/tex]
∴
In as much as [tex]e^{ \lambda x}\neq 0[/tex] for any finite [tex]\lambda[/tex]; Then:
[tex]\lambda ^3 + 9 \lambda ^2 + 111 = 0[/tex]
By Factorization:
[tex](\lambda - 3) ( \lambda ^2 + 12 \lambda + 37) = 0[/tex]
[tex]\lambda = -6 + i \ or\ \lambda = -6 - i \ or \ \lambda = 3[/tex]
However;
The root [tex]\lambda = -6 \pm i[/tex] yield;
[tex]y_1 = (x) = c_1 e ^ {(-6+i)x}[/tex]
[tex]y_2 (x) = c_2e^{(-6-i)x}[/tex]
The root [tex]\lambda = 3[/tex] yield;
[tex]y_3(x) = c_3 e^{3x}[/tex]
∴
The general solution is:
[tex]y(x) = y_1(x) + y_2(x) + y_3(x) = \dfrac{c_1}{c^{(6-i)}x}+\dfrac{c_2}{c^{(6+i)}x}+ c_3e^{3x}[/tex]
Using Euler's Identity ;
[tex]e^{\alpha+i \beta} = e^\alpha \ cos (\beta ) + i \ e^\alpha \ sin ( \beta)[/tex]
[tex]y(x) = c_1 ( \dfrac{cos (x) }{e^{6x}}+ \dfrac{i \ sin x }{e^{6x} }) + c_2 ( \dfrac{cos (x)}{e^{6x}}- \dfrac{-i \ sin (x)}{e^{6x}})+c_3 e^{3x}[/tex]
[tex]\mathbf{y(x) = \dfrac{(c_1 + c_2) \ cos (x)}{e^{6x} }+ \dfrac{i(c_1 -c_2) \ sin (x)}{e^{6x}}+ c_3e^{3\ x}}[/tex]
evaluate −2xy−1 when y=−1
Answer:
2x-1
Step-by-step explanation:
Find 8% of $40 answers with the nearest penny
Answer:
3.20
Step-by-step explanation:
Sorry i had the same question and i asked the teacher if he could help and he did but he sorta juts gave me the answer so cant really give an explanation so sorry.
The length of a table is 110 cm to the nearest cm
Write down the error interval using inequalities.
10 points for right answer
Answer: they didn’t give the exact answer.
Step-by-step explanation: they rounded to the nearest.
430tens times 30tens equals. Hundreds
Answer:
Hundreds & 100
Step-by-step explanation:
What is the image of point (-3,-1) under a reflection in the origin?
Answer:
3,1
Step-by-step explanation:
A polynomial has a leading coefficient of 1 and the
following factors with multiplicity 1:
X+2
x-√2
What is the factored form of the polynomial?
Answer:
Its A
Step-by-step explanation:
I got it right on EDGE 2021
Answer:
The answer is actually the last one
Step-by-step explanation:
I just did it. The other answer isn't even the right question.
A water-salt mixture calls for 3/4 cup if salt to be placed in 5 1/2 cups of water if i use 1 cup if salt how much water should i use to preserve the proper water to salt ratio
Answer:
7⅓ cups of water
Step-by-step explanation:
Water-salt mixture ratio = ¾ cup of salt to 5½ cups of water (¾ : 5½)
To maintain this water to salt ratio, if you intend to use 1 cup of salt, the number of water you need to add can be calculated as follows:
¾ cup of salt : 5½ cups of water = 1 cup of salt : x cups of water
¾ : 5½ = 1 : x
[tex] \frac{\frac{3}{4}}{5\frac{1}{2}}. = \frac{1}{x} [/tex]
[tex] \frac{\frac{3}{4}}{\frac{11}{2}} = \frac{1}{x} [/tex]
[tex] \frac{3}{4}*{\frac{2}{11} = \frac{1}{x} [/tex]
[tex] \frac{3}{2}*{\frac{1}{11} = \frac{1}{x} [/tex]
[tex] \frac{3*1}{2*11} = \frac{1}{x} [/tex]
[tex] \frac{3}{22} = \frac{1}{x} [/tex]
Cross multiply
[tex] 3x = 22 [/tex]
Divide both sides by 3
[tex] \frac{3x}{3} = \frac{22}{3} [/tex]
[tex] x = 7\frac{1}{3} [/tex]
Number of cups of water to add to 1 cup if salt is 7⅓ cups.
Which expression is equivalent to (65) (62)?
о
610
615
Answer: 615
Step-by-step explanation:
Jada wants to know how fast the water comes out of her faucet. what information would she need to know to be able to determine that
Answer:
Time, and Amount
Step-by-step explanation:
Well she would need to determine a time frame from within the water falling out of the tap, and how much water comes out. then she would need to observe how much water came out in that time frame, and how much time it took.
The information that Jada needs to know how fast the water comes out of her faucet include time and the amount of water.
Since Jada needs to know how fast the water comes out of her faucet include time and the amount of water. For example, let's say the amount of water coming out is 20 liters in 4 hours.
Therefore, this means the amount of water coming out per hour will be:
= 20 liters / 4 hours
= 5 liters per hour.
The main information needed is the time and the amount of water.
Read related link on:
https://brainly.com/question/17908987
Face no more through a garden and travels 1 1/8 meters in 1 1/2 minutes what is the snail’s rate in minutes per meter? HELP ME I NEED IT ASAP
Answer:
4/3 per minute
Step-by-step explanation:
Write an equation in slope-intercept form for the line that has a slope of -1 that passes through (-4,3).
Answer:
[tex]\huge\boxed{y=-x-1}[/tex]
Step-by-step explanation:
The slope-intercept form of an equation of a line:
[tex]y=mx+b[/tex]
[tex]m[/tex] - slope
[tex]b[/tex] - y-intercept
The point-slope form of an equation of a line:
[tex]y-y_1=m(x-x_1)[/tex]
[tex](x_1;\ y_1)[/tex] - point on a line
========================================
We have
[tex]m=-1;\ (-4;\ 3)\to x_1=-4;\ y_1=3[/tex]
substitute
[tex]y-3=-1(x-(-4))\\\\y-3=-(x+4)\\\\y-3=-x-4\qquad|\text{add 3 to both sides}\\\\y-3+3=-x-4+3\\\\y=-x-1[/tex]
(3+sqrt-16)(6-sqrt-64)
Answer:
12i + 9
Step-by-step explanation:
Since sqrt of negative numbers cannot exist, they are numbers followed by the letter I.
sqrt -16=4i
sqrt -64=8i
3 and 6 cannot be grouped with them, so you would add these two
3+6=9
8i+4i=12
I believe this would be the answer:
12i + 9.
Answer:
18-32i
Step-by-step explanation:
(3+sqrt(16i)(6-sqrt(64i)
= 18-32i
Please help this answer!!!!!!!!!!!!
An electrician has a 16-foot spool of wire and he needs to cut an 11-foot, 4 inch piece from the spool to make a repair. How many inches of wire will he have left on the spool after he makes the repair ?
Answer:
I might be stupid but 5 feet and 8 inches...im not positive tho. good luck
Answer && Step-by-step explanation:
just do 16-11, we also know there are 12 inches in a foot so do 12-4
5 feet, 8 inches is the answer
Find f(5). f(x) = x2 +2x
Answer:
f(5) = 35
Step-by-step explanation:
In any function f(x), x is the input and f(x) is the output
Example:
f(x) = 2x + 3, find f(a)
That means we need to find value of f(x) at x = a, so substitute x by a
f(a) = 2(a) + 3 = 2a + 3
f(a) = 2a + 3
Let us use the same way to solve our question
∵ f(x) = x² + 2x
→ We need to find f(5), so substitute x by 5
∴ f(5) = (5)² + 2(5)
∴ f(5) = 25 + 10
→ Do addition
∴ f(5) = 35
3 people take 90mins to water a garden how long does it take 6 people
Answer:
hope it is helpful
Step-by-step explanation:
mark as branlist
^ ^
Choose all the lines that are parallel to the line pictured in the graph bellow.
Answer:
a. y = -½x
b. y = -½x + 3
c. 2y = -x - 4
e. x + 2y = 8
Step-by-step explanation:
Parallel lines have the same slope. Therefore, the lines that will be parallel to the given line on the graph would have the same slope as the line of the graph.
First, find the slope of the line on the graph:
[tex] m = \frac{y_2 - y_1}{x_2 - x_1} [/tex]
Use the coordinates of any two points on the line. Let's use (-4, 0) and (0, -2)
[tex] m = \frac{-2 - 0}{0 -(-4)} = \frac{-2}{4} = -\frac{1}{2} [/tex]
Slope of the line on the graph is -½.
Check each given line equation, ensure they are in the slope-intercept form and find out if the value of their slope is the same as -½.
Slope-intercept form is given as y = mx + b, where, m = slope.
Option 1: y = -½x
The slope of this line is -½, therefore it is parallel to the line on the graph.
Option 2: y = -½x + 3
The slope of this line is also -½, therefore it is parallel to the line on the graph.
Option 3: 2y = -x - 4
Rewrite in slope-intercept form.
y = -x/2 - 4/2
y = -½x - 2
The slope of this line is -½, therefore it is parallel to the line on the graph.
Option 4: y = 2x - 5.
The slope of this line is 2, therefore it is NOT parallel to the line on the graph.
Option 5: x + 2y = 8
Rewrite in slope-intercept form.
2y = 8 - x
y = 8/2 - x/2
y = 4 - ½x
The slope of this line is -½, therefore it is parallel to the line on the graph.
Solve by substitution: y = 3x + 4 and y = -2x – 1.
Answer:
x = -1
y = 1
Step-by-step explanation:
y = 3x+4
y = -2x-1
-2x-1 = 3x+4
-5x - 1 = 4
-5x = 5
x = -1
Substitute this x value into 1 of the equations given in the problem:
y = 3(-1)+4
y = -3+4
y = 1
Answer: the answer to x= -1 and y= 1
A migrating bird flies 688 miles in 16 hours. How many miles does it fly in 5 hours?
Answer:
In 5 hours, the migrating bird will frly 215 miles.
Step-by-step explanation:
Since the bird flys 688 miles in 16 hours we need to find the unit rate. So i divided 16 by the 16 hours which gave me 1, so i also divided 688 by 16 and i got 43. So the bird flys 43 miles in a hour. We are not done yet because we need to find how many miles in 5 hours. So we multiply the 43 miles by 5 and got 215, and i also multiplied the 1 hour bye 5 and got 5. Last but not least, the migrating bird will fly 215 miles in 5 hours. I hope that this will help you out.
if $396 is invested at an interest rate of 13% per year and is compounded continuously, how much will the investment be worth in 3 years ?
Answer:
154.44
Step-by-step explanation:
What is 13% of 396?
Y is 13% of 396
Equation: Y = P% * X
Solving our equation for Y
Y = P% * X
Y = 13% * 396
Converting percent to decimal:
p = 13%/100 = 0.13
Y = 0.13 * 396
Y = 51.48
Now multiply by 3 (amount of continuous years)
51.48 * 3
=154.44
Hope it helps!
Could someone give me an answer to this please ! :)
Answer:
8units
Step-by-step explanation:
Given parameters:
Area of triangle = 32units²
Base = 8units
Unknown:
height x of the triangle = ?
Solution:
The area of a triangle is given as;
Area = [tex]\frac{1}{2}[/tex] x base x height
Input the parameters and solve for the height;
32 = [tex]\frac{1}{2}[/tex] x 8 x h
32 = 4h
h = 8
height of the triangle is 8units
A.(-2,3)
B.(-2,-3)
C.(2,3)
D.(4,3)
If two different integers between 1 and 100 inclusive are chosen at random, what is the probability that the difference of the two numbers is 15
Answer: 17 / 990
Step-by-step explanation:
To obtain the probability of the question above :
Find the count of number pairs whose difference gives is 15 in the range (1 to 100).
Also find the count of all distinct number pair differences
Number pair which have a difference of 15 = 85
Total distinct number pair differences = 4950
Probability = required outcome / Total possible outcomes
P(difference of 15) = 85/4950 = 17/990
10) Sarah is 3 years older than her sister Mary.
Together their ages add up to 23. How old is Mary?
Answer:
20
Step-by-step explanation:
20 - 3
Sarah is 3 years older so 23 is going to be subtracted.
A simple index of three socks have opening values on day 1 and day 8 as shown in the table below. What is the rate of change of this simple index over one week? Round your answer to the nearest tenth
Answer: -7.7%
Step-by- A P E X
g(x) = -4x + 5 and h(x) = x^2 - 3x + 5 find (g-h) (x)
/~—☆☆☆——☆☆☆——☆☆☆——☆☆☆——☆☆☆—~~
Answer:
−x2+g+3x−5 (I think)
Step-by-step explanation:
Plz help nothing to big but hard for me
Answer: Which question?
Step-by-step explanation:
Quickkkk!!!!!!!! Help
Answer:
2143
Step-by-step explanation: