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
[tex]f(x) = 4x + 3[/tex]
[tex]g(x) = 5x - 4[/tex]
[tex]fg(x) = 20x + p[/tex]
Find the value of
[tex]p[/tex]
Let's see
[tex]\\ \rm\rightarrowtail (fog)(x)=f(g(x))[/tex]
[tex]\\ \rm\rightarrowtail f(5x-4)=20x+p[/tex]
[tex]\\ \rm\rightarrowtail 4(5x-4)+3=20x+p[/tex]
[tex]\\ \rm\rightarrowtail 20x-16+3=20x+p[/tex]
[tex]\\ \rm\rightarrowtail -13=p[/tex]
Answer:
[tex]\sf p = -13[/tex]
Step-by-step explanation:
Given functions:
[tex]\sf f(x)=4x+3[/tex]
[tex]\sf g(x)=5x-4[/tex]
[tex]\sf fg(x)=20x+p[/tex]
[tex]\sf fg(x)=f[g(x)][/tex]
This means g(x) is substituted for x in f(x).
[tex]\sf \implies f[g(x)]=4[g(x)]+3[/tex]
[tex]\sf =4(5x-4)+3[/tex]
[tex]\sf= 20x-16+3[/tex]
[tex]\sf =20x-13[/tex]
[tex]\sf f[g(x)]=f[g(x)][/tex]
[tex]\sf \implies 20x+p=20x-13[/tex]
[tex]\sf \implies p=-13[/tex]
Madison bought b pounds of bananas and p pounds of pears and spent a total of $10.38. The price of bananas is $0.60 per pound. The price of pears is $1.74 per pound.
Create an equation that models the total amount of money that madison spend on fruit
Answer:
10.38 = 0.60b + 1.74p
Step-by-step explanation:
Ann and Makiko like to swim laps at the community center pool.
They are swimming together today (day 1), but they are on different swim schedules. Ann swims every three days and Makiko swims every five days.
Question: How many times will they both swim at the pool on the same day
during the next ten weeks (including the first day)?
please explain process and show thinking in steps.
=========================================================
Explanation:
The LCM of 3 and 5 is 3*5 = 15.
Every 15 days, the two people will swim together on the same day.
Day 1 = first day swimming togetherDay 1+15 = Day 16 = second day swimming togetherDay 16+15 = Day 31 = third day swimming togetherAnd so on.
Keep this process going of adding on 15 to find this sequence
1, 16, 31, 46, 61, 76, ...
We stop the sequence once we either reach 70 or go over it because there are 7*10 = 70 days in ten weeks. This assumes we use a 7 day week rather than a 5 day week.
As shown in bold, there are 5 items smaller than 70. So the two people swam together a total of 5 times
-----------------
Alternatively, you can solve 15n+1 = 70 for n to get n = 4.6 which rounds down to n = 4 to represent the set {0,1,2,3,4} which has 5 items in it to represent the five times total they swim together.
n = 0 corresponds to day 15n+1 = 15(0)+1 = 1n = 1 corresponds to day 15n+1 = 15(1)+1 = 16and so on until reaching n = 4 corresponding to day 15(4)+1 = 61.
A bag contains 9 tiles, each with a different number from 1 to 9. You choose a tile without looking, put it aside, choose a second tile without looking, put it aside, then choose a third tile without looking. In how many different ways can you choose three tiles
Using the combination formula, it is found that there are 84 ways to choose the three tiles.
The order in which the tiles are chosen is not important, hence the combination formula is used to solve this question.
What is the combination formula?[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by:
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
In this problem, three tiles are chosen from a set of nine, hence:
[tex]C_{9,3} = \frac{9!}{3!6!} = 84[/tex]
There are 84 ways to choose the three tiles.
More can be learned about the combination formula at https://brainly.com/question/25821700
The wholesale price desk is $153 a certain furniture store marks up the wholesale price by 38% find the price of the desk in the furniture store . Found ur answer to the nearest cent
Answer:
Step-by-step explanation:
10% = 15.30
40%=61.20
1% = 1.53
2%=3.06
61.20+3.06=64.26
153+ 64.26=217.26
One week a student exercised 3 hours at school and another of an hour at home. If of the student's total exercise came from playing basketball, how much time did the student spend playing basketball that week? Enter your answer in hours; do not include units in your answer.
Answer:
The student spent 48 minutes and 45 seconds playing basketball.
5. A triangle with a perimeter of
8 is dilated by a scale factor
of 2. What is the perimeter
of the new triangle?
Step-by-step explanation:
a scale factor normally applies to lengths (one-dimensional sizes).
the perimeter of a triangle is calculated only by using lengths, so we can apply the scaling factor directly to the perimeter.
perimeter of the new triangle = 2 × perimeter of the old triangle = 2×8 = 16
How do you calculate the diameter of a circle
Answer: "How do u calculate the diameter of a circle"?
Step-by-step explanation: Calculating diameter is easy you just need the radius, the circumference, or the area. Even if you don't have any of those dimensions, you can still find the diameter if you have a drawing of the circle.
Find the derivative of 30x² + 7x at x = 2.
Answer:
127
Step-by-step explanation:
Given :
30x² + 7xOn differentiating,
dy/dx = 2 * 30 * x²⁻¹ + 1 * 7 * x¹⁻¹dy/dx = 60x + 7At x = 2
60(2) + 7120 + 7127First differentiate
d/dx(x^n)=nx^n-1So
[tex]\\ \rm\Rrightarrow \dfrac{d}{dx}(30x^2+7x)[/tex]
[tex]\\ \rm\Rrightarrow 60x+7[/tex]
Put x=2
60(2)+7120+7127What is the slope of a line that is perpendicular to line m ?
Answer:
b) -b/a
Step-by-step explanation:
Slopes of perpendicular lines are negative reciprocals. That means to flip the fraction and change the sign. :-)
Y^2+8y+2 y=-5 evaluate the expression
Answer:
the correct answer is shown below
Step-by-step explanation:
hope this helps
have an awesome day -TJ
pls mark brainliest if this helps :)
In ΔJKL, the measure of ∠L=90°, KJ = 41, JL = 40, and LK = 9. What ratio represents the cosine of ∠J?
the question is in the attachment
Answer:
1 and 7
Step-by-step explanation:
let me know if this is helpful!
integration of csc^2(9x)dx
[tex]\displaystyle \int csc^2(9x) dx \\\\=\dfrac 19\displaystyle \int \csc^2 u ~du~~~~~~~;\left[\text{Let}~u= 9x \implies dx = \dfrac{du}9\right]\\\\=-\dfrac 19 \cot u + C\\\\=-\dfrac 19 \cot(9x)+C[/tex]
(05.02)
A line passes through (2, 8) and (4, 12). Which equation best represents the line?
oy-x+6
=
2
y = 2x + 7
y = 2x + 4
oy-*x+10
=
Answer:
⊕ y=2x+4
Step-by-step explanation:
1) all the answers are provided in slope-interception form, then
2) the slope of the required line is: (12-8)/(4-2)=2. The required line is like to y=2x+??;
3) if the points (2;8) and (4;12) belong to the line required, then the point (0;4) also belongs to this one. It means, the interception is 4;
4) finally, the line required is y=2x+4.
PS. note, the suggested solution is not the only way.
The question is below:
QUESTION -> {WHICH EQUATION DESCRIBES A LINEAR FUNCTION }.
?ANSWER :
B .
y =(1 — 6 ) ×
or.
C .
y = (2) ×
HOPE IT HELPS .
THANK ME LATER THANKS.
if log7=a and log…
help me solve ths math problem on picture
[tex]\qquad\qquad\huge\underline{\boxed{\sf Answer☂}}[/tex]
Let's solve ~
[tex]\qquad \sf \dashrightarrow \: log_{4}(39.2) [/tex]
[tex]\qquad \sf \dashrightarrow \: log_{4}( {2}^{3} \times {7}^{2} \times 10 {}^{ - 1} ) [/tex]
[tex]\qquad \sf \dashrightarrow \: log_{4}( {2}^{3} ) + log_{4}( {7}^{2} ) + log_{4}(10 {}^{ - 1} ) [/tex]
[tex]\qquad \sf \dashrightarrow \: log_{ {2}^{2} }( {2}^{3} ) + log_{ {2}^{2} }( {7}^{2} ) + log_{ {2}^{2} }(10 {}^{ - 1} ) [/tex]
[tex]\qquad \sf \dashrightarrow \: \frac{3}{2} log_{2}(2) + \frac{2}{2} log_{2}(7) - \frac{1}{2} log_{2}(10) [/tex]
[tex]\qquad \sf \dashrightarrow \: \frac{3}{2} + a - \frac{b}{2} [/tex]
That's the required result ~
also you can take it's LCM and write it as :
[tex]\qquad \sf \dashrightarrow \: \dfrac{2a - b + 3}{2} [/tex]
10. Membership to gym A is $40 per month
plus a $60 registration fee. Gym B charges
$55 per month and no registration fee.
After how many months will the
membership cost be the same?
efine the variable, write an equation, and solve
Please Help! Will Give Brainlest! Locks In an Hour! Please try again if brainly Deletes your Answer!
Answer:
The answer to your question would be -0.383
Step-by-step explanation:
I have no idea why it's deleting my answers, but that's the best choice.
If I watched anime for 1 hour a day, every episode being 20 minutes long, and there is 1016 episodes, how meant days would it take to watch the entire anime series?
Answer:
20320 minutes
Step-by-step explanation:
divided the minutes by 24 then get your answer
The interior angle of a regular polygon is 154°, What is
the size of an exterior angle?
Answer: 26 degrees
Step-by-step explanation:
An interior angle and its exterior angle are supplementary.
Kaylib’s eye-level height is 48 ft above sea level, and addison’s eye-level height is 85 and one-third ft above sea level. how much farther can addison see to the horizon? use the formula d = startroot startfraction 3 h over 2 endfraction endroot, with d being the distance they can see in miles and h being their eye-level height in feet. startroot 2 endroot mi 2 startroot 2 endroot mi 14 startroot 2 endroot mi 28 startroot 2 endroot mi
The addison see to the horizon at 2 root 2mi.
We have given that,Kaylib’s eye-level height is 48 ft above sea level, and addison’s eye-level height is 85 and one-third ft above sea level.
We have to find the how much farther can addison see to the horizon
Which equation we get from the given condition?[tex]d=\sqrt{\frac{3h}{2} }[/tex]
Where, we have
d- the distance they can see in thousands
h- their eye-level height in feet
For Kaylib
[tex]d=\sqrt{\frac{3\times 48}{2} }\\\\d=\sqrt{{3(24)} }\\\\\\d=\sqrt{72}\\\\d=\sqrt{36\times 2}\\\\\\d=6\sqrt{2}....(1)[/tex]
For Addison h=85(1/3)
[tex]d=\sqrt{\frac{3\times 85\frac{1}{3} }{2} }\\d\sqrt{\frac{256}{2} } \\d=\sqrt{128} \\d=8\sqrt{2} .....(2)[/tex]
Subtracting both distances we get
[tex]8\sqrt{2}-6\sqrt{2} =2\sqrt{2}[/tex]
Therefore, the addison see to the horizon at 2 root 2mi.
To learn more about the eye level visit:
https://brainly.com/question/1392973
Answer:
2 root 2mi.
Step-by-step explanation:
Edge2020
Identify the equation that describes the line in slope-intercept form.
slope = 3, point (−2, −4) is on the line.
choices:
y = 3x − 10
y = 3x − 4
y = 3x + 2
y = 3x − 2
Pls help im in a test
Describe the relationship between pi and circles.
Answer:
The circumference (C) of a circle is found by the equation C = 2*[tex]\pi[/tex]*radius
There is a second relationship between [tex]\pi[/tex] and circles. That of the area (A) of the circle which is found by the formula A = [tex]\pi*radius^{2}[/tex]
Step-by-step explanation:
Express as in Kg using decimals.
a) 12 g. b) 7 g.
c) 35 kg 15 g. d) 675 g
Answer:
a)0.012 kg
b)0.007kg
c)35.015kg
d)0.675kg
Step-by-step explanation:
please mark me as brainlest
What is the probability of rolling a sum of 8 with a pair of dice?
Answer:
[tex]\frac{5}{36}[/tex]
Step-by-step explanation:
the total number of possible combinations of rolling two dice is 36 because a side has 6 sides and [tex]6^{2}=36[/tex]
and possible combinations that sum to 8 are
2 and 63 and 54 and 45 and 36 and 2which are 5 possible combinations which gives [tex]\frac{5}{36}[/tex]
What is the length of the sides of kite abcd? ab = 20; cd = 15 ab = 15; cd = 20 ab = 9; cd = 16 ab = 24; cd = 25
The length of the side AB and side CD of kite abcd which is shown in the figure is 15 units and 20 units respectively.
What is Pythagoras theorem?Pythagoras theorem says that in a right angle triangle the square of hypotenuse side is equal to the sum of square of other two legs of right angle triangle.
Let the intersection point of dignoals is O. The figure of the kite ABCD, is attached below. The sides of the kite ABCD, are,
[tex]AO=12\\OB=9\\CO=12\\OD=16[/tex]
In the triangle AOB using the pythagours theorem,
[tex]AB=\sqrt{(AO)^2+(OB)^2}\\AB=\sqrt{(12)^2+(9)^2}\\AB=\sqrt{225}\\AB=15[/tex]
Similarly, in the triangle DOC using the pythagours theorem,
[tex]CD=\sqrt{(CO)^2+(OD)^2}\\CD=\sqrt{(12)^2+(16)^2}\\CD=\sqrt{400}\\CD=20[/tex]
Thus, the length of the side AB and side CD of kite abcd which is shown in the figure is 15 units and 20 units respectively.
Learn more about the Pythagoras theorem here;
https://brainly.com/question/343682
Answer:
its B
Step-by-step explanation:
Mrs.martin's class has 8 boys out of a total of 20 students.which is the ratio of girls to boys in her class?
Answer:
8:20 or if you want it simplified 2:5
Step-by-step explanation:
Use the explicit rule to find a12. an=-2n+8
The explicit rule formula an = -2n + 8 is an arithmetic progression
The value of a11 is -14
How to evaluate the explicit rule?The explicit rule formula is given as:
an = -2n + 8
Substitute 11 for n to calculate a11
a11 = -2 * 11 + 8
Evaluate the product
a11 = -22 + 8
Evaluate the sum
a11 = -14
Hence, the value of a11 is -14
Read more about explicit rules at:
https://brainly.com/question/12119793
show your work please :(
Answer:
you cant see the picture
Step-by-step explanation: