Answer:
0.50 seconds
Step-by-step explanation:
The time it takes for an echo to return is the time it takes for the sound to make the round trip between the source and the reflecting object.
The boulder is 80 m away from the source, so the round-trip distance is 2×80 m = 160 m. At a speed of 320 m/s, it takes sound ...
(160 m)/(320 m/s) = 0.50 s
to make the round-trip.
It will take 0.50 seconds to hear the echo.
The time it will take to hear the echo, when the speed of a sound wave is 320 m/s is 0.50 seconds.
What is the speed of sound?
Speed of sound is the rate by which the sound wave travels. The speed of sound depends on the medium by which the sound wave is travelling.
The speed of the wave can be found out using the following formula.
[tex]s=\dfrac{d}{t}[/tex]
Here, (d) is the distance travelled by the wave and (t) is time taken by the wave to cover that distance.
A boy yells in a narrow valley. The sound reflects off of a boulder that is 80 m away.
For the echo, distance travelled will be doubled as it come back.Thus, the distance travelled by sound wave is,
[tex]d=2\times80\\d=160\rm\; m[/tex]
The speed of sound is 320 m/s. Put these value in the above formula as,
[tex]320=\dfrac{160}{t}\\t=0.5\rm\; s[/tex]
Thus, the time it will take to hear the echo, when the speed of a sound wave is 320 m/s is 0.50 seconds.
Learn more about the speed of sound here;
https://brainly.com/question/95976
Tamara attends a cycling class that starts at 6:00. The class lasts 45 minutes. What time does class end?
Group of answer choices
A.15 minutes before 7:00
B.15 minutes after 6:00
C.45 minutes before 7:00
D.45 minutes after 7:00
Answer: C. 45 minutes before 7:00
Hope this helps! :)
Brainliest please.
I just took a test and my brain is fried please help thanks
[tex]tan(\theta )=\sqrt{3}\implies tan(\theta )=\cfrac{\sqrt{3}}{1}\implies tan(\theta )=\cfrac{\sqrt{3}}{1}\cdot \cfrac{2}{2} \implies tan(\theta )=\cfrac{\sqrt{3}}{2}\cdot \cfrac{2}{1} \\\\\\ tan(\theta )=\cfrac{~~\stackrel{sin(\theta )}{\frac{\sqrt{3}}{2}} ~~}{\underset{cos(\theta )}{\frac{1}{2}}}\implies \theta =tan^{-1}\left( \cfrac{~~\frac{\sqrt{3}}{2} ~~}{\frac{1}{2}} \right)\implies \theta = \begin{cases} \stackrel{I~Quadrant}{60^o}\\\\ \stackrel{III~Quadrant}{240^o} \end{cases}[/tex]
Check the picture below.
Find the radius of a circle with area of 452.4 mi2
Answer:
r≈12mi
Step-by-step explanation:
mark brainiest and Im 100% correct
A restaurant manager gives a survey to all of his customers asking them to rate the quality of the service they received. He then keeps track of how many customers return to the restaurant during the next six months. Last year, the results showed that of the customers who reported high quality service, 90% returned for additional meals. What conclusion can be drawn from this study? (6 points) Only some customers who rate their service as high quality return for additional meals. Most customers who rate their service as high quality return for additional meals. High quality services cause customers to return for additional meals. Customers who will return for additional meals report a high quality of service.
Answer: High quality services cause customers to return for additional meals.
Step-by-step explanation: The 90% crosses out the first option. Because it's 90% we don't know if all the customers reported their service. The last one just to me wouldn't make sense.
Liz's tea was too hot to drink, so she put it in the freezer. The temperature of the tea was
initially 175°F, and it decreased by about 7% each minute. You can use a function to approximate the
temperature of Liz's tea X minutes after she put it in the freezer.
Which equation represents this function?
The answer for this equation funtion would be The first one because it is the correct answer.
Answer:
Step-by-step explanation:
given that 2x^2 - 2y^2 = 40 and x-y=5, find the value of (x+y)
Answer:
x+y=4
Step-by-step explanation:
hello :
note : by identity you have x²-y² = (x-y)(x+y)
in this exercice : 2x²-2y² = 2(x²-y²) = 2 (x-y)(x+y)
means : 2 (x-y)(x+y) = 40
but x-y = 5
so : 2(5)(x+y) =40
x+y=40/10
x+y=4
find the value of x, round to the nearest 10th
I will give brainliest
A cylinder has a volume of 320 pi cubic inches and a height of 5 inches what is the radius
Answer:
As Per Provided Information
A cylinder has a volume of 320 pi cubic inches and a height of 5 inches.
We have been asked to determine the radius of the cylinder .
Using Formulae
[tex] \purple{\boxed {\bf\: Volume_{(Cylinder)} = \pi {r}^{2}h}}[/tex]
Substituting the value and let's solve for radius .
[tex] \sf \qquad \longrightarrow \: 320 \pi \: = \pi \: \times r {}^{2} \: \times 5 \\ \\ \\ \sf \qquad \longrightarrow \:320 \cancel{\pi} = \cancel{ \pi} \times r {}^{2} \: \times 5 \\ \\ \\ \sf \qquad \longrightarrow \:320 = r {}^{2} \: \times 5 \\ \\ \\ \sf \qquad \longrightarrow \:r {}^{2} \: = \cfrac{320}{5} \\ \\ \\ \sf \qquad \longrightarrow \: {r}^{2} = \cancel\cfrac{320}{5} \\ \\ \\ \sf \qquad \longrightarrow \: {r}^{2} = 64 \\ \\ \\ \sf \qquad \longrightarrow \:r \: = \sqrt{64} \\ \\ \\ \sf \qquad \longrightarrow \:r \: = 8 \: inch[/tex]
Therefore,
Radius of cylinder is 8 Inches .HELP
Manny kept track of the number of home runs he hit every year in high school.
{11, 10, 17, 18)
What is the mean absolute deviation (MAD) of the data set?
Enter your answer in the box. Round to the nearest tenth, if necessary.
Answer:
Ok, to find MAD, you have to add up all of the decimals in the set, and then divide by how much decimals there are in the set.
Adding them all up...
The final result of the adding is 56.7
Now, we have to divide by how much decimals.
We now have. 56.7 / 6
Do the division.
56.7 / 6 ===> 9.45
No need to round, the final answer is 9.4
cereal set roster notation
Answer:
Step-by-step explanation:
Notation for Cereal Set Roster
The roster form is one of the simplest ways to represent the set. The elements of a set are represented in a row and separated by a comma in roster form. For example, the first five positive even numbers are denoted as A = 2, 4, 6, 8, 10.
A = 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100 is an example of roster notation: A = 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100.
Hope that helps you understand :)
HELP PLEASE!! <3
i honestly don't understand what they want me to do here
Answer:
(a)
Step-by-step explanation:
the equation of a circle centred at the origin is
x² + y² = r² ( r is the radius )
x² + y² = 20 ← is in this form , then
centre = (0, 0 ) and r = [tex]\sqrt{20}[/tex] = [tex]\sqrt{4(5)}[/tex] = [tex]\sqrt{4}[/tex] × [tex]\sqrt{5}[/tex] = 2[tex]\sqrt{5}[/tex]
pls help me to answer this
I'll do the first two questions of each activity to get you started. The remaining unanswered questions will follow similar steps compared to the other questions in the same activity group.
=======================================================
Activity 5, Problem 1
To find the mean, we first add up the values
4+8+2+8+5+9 = 36
Then we divide over n = 6 because there are 6 values in this data set.
36/n = 36/6 = 6
Answer: Mean = 6=======================================================
Activity 5, Problem 2
Follow the same idea as the previous problem.
Add the values: 9+8+8+13+12 = 50
Divide by the number of values: 50/n = 50/5 = 10
Answer: Mean = 10=======================================================
Activity 6, Problem 1
The median is the middle-most number. Think of a median of a highway or freeway.
In order to find the median, we first need to sort the data values from smallest to largest.
The original set {7,3,9,9,2,5,8} sorts to {2, 3, 5, 7, 8, 9, 9}
If we erased the first and last items, we get this smaller subset
{3, 5, 7, 8, 9}
repeat again to get
{5,7,8}
At this point its clear the middle most value is 7
But if you wanted, you could cross the first and last values from the list to end up with {7}
Answer: Median = 7=======================================================
Activity 6, Problem 2
We could do the same trick as the previous problem, but I'll use a slightly different route this time.
We'll need to sort {10,8,4,11,9} into {4, 8, 9, 10, 11}
There are n = 5 items in that set. The middle slot would be at slot n/2 = 5/2 = 2.5 = 3
The value 9 is in slot 3 of the sorted items.
Answer: Median = 9=======================================================
Activity 7, Problem 1
The mode is the most frequent value of a set. It repeats the most often.
The set {5,6,7,3,5,4} sorts to {3,4,5,5,6,7}
The value "5" shows up the most. It shows up twice when everything else shows up exactly once only.
Answer: Mode = 5=======================================================
Activity 7, Problem 2
Using the same idea in the previous problem, the set {7,4,11,9,7,3} has the mode 7 because it shows up the most of any other value.
Here's the sorted set: {3,4,7,7,9,11}
Sorting is optional with finding the mode in contrast to being mandatory when it comes to finding the median.
Answer: Mode = 7Need help with b please and thank you (lots of points)
Answer:
17.34 years
Step-by-step explanation:
The equation you wrote in the first part of the problem can be solved for the value of t that makes the population be 5000.
[tex]P(t)=\dfrac{10000}{1+11.5e^{-0.1408614477t}}[/tex]
Setting this equal to 5000 and multiplying by the denominator, we have ...
[tex]5000=\dfrac{10000}{1+11.5e^{-0.1408614477t}}\\\\5000+57500e^{-0.1408614477t}=10000\\\\e^{-0.1408614477t}=\dfrac{5000}{57500}\qquad\text{subtract 5000, divide by 57500}\\\\-0.1408614477t = \ln{\dfrac{1}{11.5}}=-\ln(11.5)\qquad\text{take logs}\\\\t=\dfrac{\ln(11.5)}{0.1408614477}\approx17.3386[/tex]
For the population to reach 5000, it will take about 17.34 years.
_____
Additional comment
The value -0.14086... is the natural log of the ratio 1818/2093. This means the "exact answer" is ln(11.5)/(ln(2093) -ln(1818)), an irrational number.
A graphing calculator can answer the question easily.
He wallow fire of 2011 burned 538,000 acres in eastern arizona. A. [2 pts] if one square mile is 640 acres, how many square miles did the fire burn?
The square miles that was burned if one square mile is 640 acres is 840.625 square miles.
What does division mean?Division is the process of grouping a number into equal parts using another number. The sign used to denote division is ÷. Division is one of the basic mathematical operations.
How many square miles was burned?Square miles that was burned = 538,000 / 640 = 840.625 square miles
To learn more about division, please check: https://brainly.com/question/13281206
There are 840.625 square miles did the fire burn.
What is division?Division is the process of sharing a collection of items into equal parts and is one of the basic arithmetic operations in maths.
The wallow fire of 2011 burned 538,000 acres in eastern Arizona.
The area of square miles did the fire burned is;
[tex]\rm Area =\dfrac{538,000}{640}\\\\Area =840.625 \ square \ miles[/tex]
Hence, there are 840.625 square miles did the fire burn.
To learn more about division here:
brainly.com/question/13281206
#SPJ4
please help i will give brainly?
Which of the following can be written as an expression? Select all that apply.
Half the difference of 5 and 3
7 is less than twice x.
Five and a half times x is 44.
Twice the product of 3 and 8
5 less than x
Answer:
5-3/22x-75 1/2x = 442(3x8)X-5Explain how you can tell if the expressions 7x – 4 and 6x – 4 – x are equivalent.
Hey there!
Combine Like Terms and see if the expressions are equivalent or not.
6x-4-x
6x-x-4
5x-4
Is 5x-4 equivalent to 7x-4? No.
Hope everything is clear.
Let me know if you have any questions!
Always remember: Knowledge is power!
Answer:
Given; 7x – 4 and 6x – 4 – x
To Find; how you can tell if the expressions 7x – 4 and 6x – 4 – x are equivalent
Solution; This question can be easily solved by letting some value of x and putting in both the equation to check whether both are equal or not
Let x=1
7x-4=3 and 5x-4=1
Since both are not equal Hence the given equations are not equalnation:
CAN SOMEONE PLEASE HELP ME ITS DUE TODAY
[tex] \qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]
Here we go ~
To find Highest common factor (HCF) we have to check what primes are common between them along with their exponent. And multiply them ~
here, we get [ 2³ and 3 as common ]
[tex]\qquad \sf \dashrightarrow \:HCF = {2}^{3} \times 3 [/tex]
[tex]\qquad \sf \dashrightarrow \:HCF = {8}^{} \times 3 [/tex]
[tex]\qquad \sf \dashrightarrow \:HCF = 24[/tex]
So, HCF of the given numbers is 24
Heather has a bag containing 4 marbles: 1 red, 1 blue, and 2 green. she draws 1 marble out of the bag, replaces it, and then draws another marble. what is p(red then blue then green)?
Multiply the probability of each by each other:
Probability of red = 1/4
Probability of blue = 1/4
Probability of green = 2/4 = 1/2
probability of red then blue then green = 1/4 x 1/4 x 1/2 = 1/32
answer: 1/32
Help literally fast at possibly
Answer:
Yes you want to do it again soon
What is the answer for this question?
Answer:
64 cm³
Step-by-step explanation:
The volume of a cube is an edge cubed. Since all the sides/edges are the side, you do 4 * 4 * 4 which gets 64
GUYS I NEED HELP ASAP IVE BEEN STUCK ON THIS MATH PROBLEM
The cylinder shown has a volume of 695 cubic inches.
What is the radius of the cylinder?
Step-by-step explanation:
[tex]volume = \pi {r}^{2}h[/tex]
[tex]695 = 3.14 \times {r}^{2} \times 11.5[/tex]
[tex] {r}^{2} = 19.2[/tex]
[tex]r = \sqrt{19.2} = 4.3[/tex]
A farmer plants wheat and corn. It costs about $150 per acre to plant wheat and about $350 per acre to plant corn. The farmer plans to spend no more than $250,000 planting wheat and corn. The total area of corn and wheat that the farmer plans to plant is less than 1200 acres
The inequality that models this situation is 150x + 350 y ≤ 250000 and x + y < 1200
What is an inequality?
An inequality is an expression that shows the non equal comparison of two or more numbers and variables.
Let x represent the number of wheat acres and y represent the number of corn acres, hence:
150x + 350 y ≤ 250000 (1)
Also:
x + y < 1200 (2)
The inequality that models this situation is 150x + 350 y ≤ 250000 and x + y < 1200
Find out more on inequality at: https://brainly.com/question/24372553
PLEASE HELP QUICK
9) Which of these MOST helped J.R.R. Tolkien to become a successful writer?
A) His sense of humor.
B) His loving children.
©) His creative imagination.
D) His appetite for success.
Answer: C) His creative imagination
Step-by-step explanation:
J.R.R. Tolkien's creative imagination most helped him to become a successful writer
Solve each equation.
Equation 1: x=32
Equation 2: y=28
Answer:
x = 32
x = 28
Step-by-step explanation: hope this helps
8. Harper, Elie, and Raina are having a skateboard race. Harper began at the starting line and rode at a
constant rate of 3 feet per second. Elie got a five-foot head start and rode two feet every 3 seconds. Raina
rode 3 feet every five seconds and had a two-foot head start.
Answer:
Step-by-step explanation:
don’t even know how i got this far in geometry lol
[tex]\qquad\qquad\huge\underline{{\sf Answer}}☂[/tex]
Let's find the Area of sector ~
[tex]\qquad \sf \dashrightarrow \: \dfrac{ \theta}{360} \times \pi{r}^{2} [/tex]
[tex]\qquad \sf \dashrightarrow \: \dfrac{ 270}{360} \times \pi{6}^{2} [/tex]
[tex]\qquad \sf \dashrightarrow \: \dfrac{ 3}{4} \times {36}^{} \pi[/tex]
[tex]\qquad \sf \dashrightarrow \:3 \times 9 \pi[/tex]
[tex]\qquad \sf \dashrightarrow \:27\pi \: \: ft {}^{2} [/tex]
NEED HELP ASAP!!!! GIVING BRAINLIEST+ 30 POINTS TO WHOEVER CAN ANSWER THESE TWO QUESTIONS THE BEST!!!
Answer:
For question 2: 15/4.
For question 3: 10/8.
Step-by-step explanation: To multiply fractions, you multiply the numerators and then the denominators. We should first transform any whole numbers into fractions. The first step is done below:
For question 2: 5 to 5/1.
For question 3: 2 to 2/1.
Now, we can multiply the numerators and denominators to answer the following:
For question 2: 5/1 x 3/4. The numerators are 5 and 3, so multiply those to get 15. The denominators are 1 and 4, so multiply those to get 4. Your answer is 15/4.
For question 3: 2/1 x 5/8. The numerators are 2 and 5, so multiply those to get 10. The denominators are 1 and 8, so multiply those to get 8. Your answer is 10/8.
Let me know if this is right! :)
Si Adrián tiene “x” años de edad, Teresa la tercera parte de Adrián, Isabel el doble de Teresa y Felipe el cuádruple de Adrián, ¿cuánto suman las edades de los cuatro? Selecciona el inciso correcto.
the answer is ISABELLA YOUR BOYFRINDS HERE
The sales tax is $14 per
$100 What percent is the
sales tax? Show your
work.
NEED HELP ASAP PLEASE
Answer:
14%
Step-by-step explanation:
lets whip out that EPIC CALCULATOR! alright so i hope that you have your calculator with you, whether it is a physical one or a digital one on your computer.
try this:
enter 14, then the division sign ( could be a ÷ or an / ) and then 100.
what do we get?
0.14
ok, now lets multiply this by 100 to get the PERCENT instead of the DECIMAL, and we get
14%
EPIC!