Answer:
The slower plane has a speed of 450 km/h and the faster one has a speed of 900 km/h.
Step-by-step explanation:
Two planes:
The first one's speed is x
The second is y.
One plane is flying at twice the speed of the other.
I will say that y = 2x.
Two airplanes leave an airport at the same time, flying in the same direction
Same direction, so their relative speed is the subtraction of their speeds. 2x - x = x.
Means that after 1 hour, they will be x miles apart.
If after 4 hours they are 1800 km apart, find the speed of each plane
After 1 hour, x km apart. After 4, 1800. So
1 hour - x km apart
4 hours - 1800 km apart
4x = 1800
x = 1800/4
x = 450
2x = 2*450 = 900
The slower plane has a speed of 450 km/h and the faster one has a speed of 900 km/h.
You are studying a population of squirrels on the south rim of the Grand Canyon and find that 9 squirrels out of 100 observed had a unique, solid black color variation. In other mammals, the solid black color variation is caused by a recessive allele, and you assume that to be the case with these squirrels. If the population is in Hardy-Weinberg equilibrium, which of the following would be true?
A. q2 = 0.09
B. .q2 = 0.9
C. The frequency of the black color allele is 0.3, the frequency of the dominant allele is 0.7
D. The frequency of the heterozygous genotype is 4.2%
E. A and C
Which of the following is/are possible applications for use of the CRISPR-Cas9 system?
A. Disable dominant deleterious genes
B. Turn on and off specific genes by disabling Cas9 nuclease activity and attaching it to a transcriptional activator or repressor protein
C. Study gene function
D. all of the above
Genome wide association studies are important for behavioral disorders because
A. Candidate genes can be identified for further study
B. They provide an association between genetic loci and phenotypes
C. They provide a tool to help understand how genetic and environmental factors interact to cause psychiatric disorders
D. all of the above
Answer:
Step-by-step explanation:
Ans-1.)
q 2 = 9 /100 (A) q = 0.3 (p + q) 2 = 1 p + q = 1 p = 1- q = 1 - 0.3 p = 0.7 * The frequency of black color allele is 0.3 and dominant allele is 0.7 (C)
* (A) and (C)Ans -2.) CRISPR -Cas 9 system has very wide application :
* can be used to disable the dominant deleterious genes .
* Turn on and off by disabling Cas9 nuclease activity and attaching to a transcriptional activator or repressor protein.
* widely used to study function
* All the above (answer)Ans-3.) Genome wide association studies are important to study behavioral disorders because
* candidate genes identified for further studies.
* Provide an association between genetic loci and phenotypes.
* Provide a tool to help understand how genetic and environmental factors interact to pyschiatric disorders
* All of the above (answer)Data on return-to-pay ratios was collected from CEOs of companies within both the low-tech industry and the consumer products industry.
Low-Tech Consumer Products
Sample size 14 12
Sample mean 157 218
Sample Variance 1563 1602
Assume population variances are unequal.
(a) The point estimate of the difference between the means of the two populations is
(b) The standard error for the difference between the two means is
(c) The correct distribution to use is :
t-distribution with 26 degrees of freedom
t-distribution with 23 degrees of freedom
normal distribution
t-distribution with 24 degrees of freedom
Answer:
Step-by-step explanation:
The confidence interval for the difference of two population means is expressed as
Confidence interval = (x1 - x2) ± z√(s²/n1 + s2²/n2)
Where
x1 = sample mean of low-tech industry
x2 = sample mean of consumer products industry
s1 = sample standard deviation low-tech industry
s2 = sample standard deviation for consumer products industry
n1 = number of samples of low-tech industry
n2 = number of samples of consumer products industry
a) x1 - x2 is the point estimate of the difference between the means of the two populations
Therefore,
Point estimate = 157 - 218 = - 61
b) the formula for standard error is expressed as
√(s1²/n1 + s2²/n2)
Variance = standard deviation²(s²)
s1² = 1563
s2² = 1602
Standard error = √(1563²/14 + 1602²/12) = 623.2
c) Degree of freedom =
(n1 - 1) + (n2 - 1) = (14 - 1) + (12 - 1) = 24
t-distribution with 24 degrees of freedom
According to the data given, we have that:
a) 61
b) 15.65
c) t-distribution with 24 degrees of freedom
Item a:
The point estimate is the difference between the two sample means, hence:
218 - 157 = 61.
Item b:
For each sample, the standard errors are:
[tex]s_l = \sqrt{\frac{1563}{14}} = 10.57[/tex]
[tex]s_h = \sqrt{\frac{1602}{12}} = 11.54[/tex]
For the difference of the two means, it is:
[tex]s = \sqrt{s_l^2 + s_h^2} = \sqrt{10.57^2 + 11.54^2} = 15.65[/tex]
Item c:
Samples of 14 and 12, hence 14 + 12 - 2 = 24 df.
A similar problem is given at https://brainly.com/question/12490448
1. An LG Dishwasher, which costs $800, has a 20% chance of needing to be replaced in the first 2 years of purchase. A two-year extended warrantee costs $112.10 on a dishwasher. What is the expected value of the extended warranty assuming it is replaced in the first 2 years?
2. Approximately 10% of all people are left-handed. Consider a grouping of fifteen (15) people.
a. State the random variable.
b. Write the probability distribution.
c. Draw a histogram.
d. Describe the shape of the histogram.
e. Find the mean.
f. Find the variance.
g. Find the standard deviation.
Step-by-step explanation:
The expected value of the extended warrant is calculated as follow.
Value of Waranty
= 800 x 20% − 112.10
= 800 x 20/100 − 112.10
= 47.9
The expected value of the extended warranty assuming it is replaced in the first 2 years is given as follow.
Expected value=800-112.10=>687.90
Therefore, required expected value of extended warranty is 687.90
2.
Given information:
Number of Trials (n) = 15
Probability of Success (p) = 0.10
a) Let X represents the number of left-handed people.
b) The probability distribution follows binomial distribution.
X ∼ Binomial distribution
The probability distribution is given as follow.
P(X = x) = ^nCx(p)^x(1 − p)^n − x
c)The histogram is given as follow. (See attachment)
d) The shape of histogram is skewed right.
e) The mean is calculated as follow.
Mean
=n x p
= 15 x 0.10
= 1.5
f) The variance is calculated as follow.
Variance
= n x p x q
= 15 x 0.10 x 0.90
= 1.35
g) The standard deviation is calculated as follow.
Standard deviation
=√n x p x q
=√15 x 0.10 x 0.90
= 1.162
(a) Use a linear approximation to estimate f(0.9) and f(1.1). f(0.9) ≈ f(1.1) ≈ (b) Are your estimates in part (a) too large or too small? Explain. The slopes of the tangent lines are negative, but the tangents are becoming steeper. So the tangent lines lie below the curve f. Thus, the estimates are too large. The slopes of the tangent lines are negative, but the tangents are becoming steeper. So the tangent lines lie below the curve f. Thus, the estimates are too small. The slopes of the tangent lines are positive, but the tangents are becoming less steep. So the tangent lines lie above the curve f. Thus, the estimates are too large. The slopes of the tangent lines are positive, but the tangents are becoming less steep. So the tangent lines lie above the curve f. Thus, the estimates are too small.
Answer:
(Missing part of the question is attached)
[tex]L(x)=2x+3[/tex]
Estimates are too large.
Step-by-step explanation:
Suppose the only information we know about the function is:
[tex]f(1)=5[/tex]
where the graph of its derivative is shown in the attachment
(a)If the function [tex]f\\[/tex] is differentiable at point [tex]x=1[/tex] , the tangent line to the graph of [tex]f[/tex] at 1 is given by the equation:
[tex]y=f(1) +f'(1)(x-1)[/tex]
So we call the linear function:
[tex]L(x)=f(1) +f'(1)(x-1)[/tex]
We know the [tex]f(1)=5[/tex] as it is given in the question, and [tex]f'(1)=2[/tex] from the graph attached. Substitute in the equation of [tex]L(x)[/tex].
[tex]L(x)=5+2(x-1)\\L(x)=5+2x-2\\L(x)=2x+3\\[/tex]
(b)At x=1, [tex]f'(x)[/tex] is positive but it is decreasing. However. if we draw the tangent lines, we see that the tangent lines are becoming less steeper, so the tangent lines lie above the curve [tex]f[/tex]. Thus, The estimates are too large.
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
a
Step-by-step explanation:
because as absolute value gets smaller the line gets steeper
r
9. ABCD is a square and ABK is an equilateral triangle outside the square,
Find measurment of angle DKC
Answer:
< DKC = [tex]60^{0}[/tex]
Step-by-step explanation:
A square is a quadrilateral that has equal length of side. While an equilateral triangle is one with equal length of sides and equal values of angles.
Given square ABCD and that equilateral triangle ABK is outside the square, both figures share side AB. This shows that the length of the sides of the triangle is the same as the length of the side of the square.
i.e /AD/ = /CD/ = /BC/ = /AB/ = /AK/ = /KB/
Thus, < DKC = [tex]60^{0}[/tex] (property of angles in an equilateral triangle)
Find the missing side. Round to
the nearest tenth.
x
9
28°
x = [?]
Answer:
19.2
Step-by-step explanation:
It's right on Acellus.
The required value of x nearest to tenth is 19.17
What is hypotenuse?The longest side of the right angled triangle is called hypotenuse
By the Pythagoras theorem in the right angled triangle
h^2 = b^2 + p^2
where h = hypotenuse, b = base, p = perpendicular
How to calculate hypotenuse?Here we have given perpendicular p = 9
and an angle = 28°
Using sin for the given angle we have
sin 28° = [tex]\frac{perpendicular}{hypotenuse}[/tex]
0.46947 = [tex]\frac{9}{x}[/tex]
x = [tex]\frac{9}{0.46947}[/tex]
x = 19.17
Hence the required length of the side hypotenuse = x = 19.17
This is the conclusion to the answer.
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my last question and im done, please help!
Answer:
2 acute and one right.
Step-by-step explanation:
plz mark brainliest!
Answer:
2 acute 1 right, you asked for ASAP so theres no explanation
You cant mix right and obtuse, and you cant have more than 1 obtuse in a triangle. There has to be at least 2 acute angles.
B point is (-5,-4) moves through the translation (x+1 , y-3) what will be the coordinates of B
Answer:
(-4,-7)
Step-by-step explanation:
Adding 1 to the x and subtracting 3 from the y we get
-5+1= -4
And
-4-3= -7
A city has 5 new houses for every 7 old houses. If there are 45 new houses in the city, how many old houses are there?
Answer:
63
Step-by-step explanation:
Make a ratio:
5 : 7 = 45 : x
x = 63
Bernard bought 8gal of paint. Convert the volume to liters. Round to the nearest tenth
Answer:
In one gallon of paint there are about 3.8 liters so 8 gallons is about 30.3 liters.
Borland, Inc., has a profit margin of 5.6 percent on sales of $13.6 million. If the firm has debt of $6.4 million and total assets of $9.8 million, what is the firm’s ROA?
Answer:
ROA = 7.77 percent
Step-by-step explanation:
Borland, Inc., has a profit margin of 5.6 percent on sales of $13.6 million
Thus, profit = 5.6% of $13.6 million
profit = 5.6 / 100 * $13.6 million = $0.7616 million
Profit is same as net income
Formula for ROA (return on asset) = net income/ total asset
total asset as given = $9.8 million
Thus, ROA = $0.7616/ $9.8 = 0.0777
ROA in percentage = 0.0777*100 = 7.77
Thus, ROA is 7.77 percent .
A spinner with 6 colors is spun and a number cube is tossed determine the number of outcomes
Answer:
36
Step-by-step explanation:
since there are six outcomes for the spinner and six outcomes for the cube,
6 x 6 = 36
The width of the rectangle is 2 more than the length. The area of the rectangle is 63 square inches. How long is the width?
Answer:
9 inches
Step-by-step explanation:
Area of rectangle= length ×width
Let the length of the rectangle be x inches.
Width of rectangle= (x +2) inches
since the width is 2 more than the length.
63= x(x+2)
63= x(x) +2x
Bringing constant to one side,
x² +2x -63= 0
(x +9)(x-7) = 0 (factorise)
x+9= 0 or x-7= 0
x= -9 or x= 7
(reject)
width of rectangle
= 7+2
= 9 inches
*We reject x= -9 since the length of the rectangle cannot be a negative number.
According to a report released by CIBC entitled "Women Entrepreneurs: Leading the Charge," the average age for Canadian businesswomen in 2008 was 41. In the report, there was some indication that researchers believed that this mean age will increase. Suppose now, a few years later, business researchers in Canada want to test to determine if, indeed, the mean age of Canadian businesswomen has increased. The researchers randomly sample 97 Canadian businesswomen and ascertain that the sample mean age is 43.4. From past experience, it is known that the population standard deviation is 8.95. Test to determine if the mean age of Canadian businesswomen has increased using a 1% level of significance. What is the p-value for this test? What is the decision? If the null hypothesis is rejected, is the result substantive?
Answer:
We conclude that the mean age of Canadian businesswomen has increased.
Step-by-step explanation:
We are given that according to a report released by CIBC entitled "Women Entrepreneurs: Leading the Charge," the average age for Canadian businesswomen in 2008 was 41.
The researchers randomly sample 97 Canadian businesswomen and ascertain that the sample mean age is 43.4. From past experience, it is known that the population standard deviation is 8.95.
Let [tex]\mu[/tex] = mean age of Canadian businesswomen.
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] [tex]\leq[/tex] 41 {means that the mean age of Canadian businesswomen has decreased or remained same}
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu[/tex] > 41 {means that the mean age of Canadian businesswomen has increased}
The test statistics that would be used here One-sample z-test statistics because we know about population standard deviation;
T.S. = [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] ~ N(0,1)
where, [tex]\bar X[/tex] = sample mean age of Canadian businesswomen = 43.4
[tex]\sigma[/tex] = population standard deviation = 8.95
n = sample of Canadian businesswomen = 97
So, the test statistics = [tex]\frac{43.4-41}{\frac{8.95}{\sqrt{97} } }[/tex]
= 2.64
The value of z test statistic is 2.64.
Also, P-value of the test statistics is given by;
P-value = P(Z > 2.64) = 1 - P(Z < 2.64)
= 1 - 0.99585 = 0.00415
Now, at 1% significance level the z table gives critical value of 2.33 for right-tailed test.
Since our test statistic is more than the critical value of z as 2.64 > 2.33, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.
Therefore, we conclude that the mean age of Canadian businesswomen has increased.
A ball travels on a parabolic path in which the height (in feet) is given by the expression $-25t^2+75t+24$, where $t$ is the time after launch. At what time is the height of the ball at its maximum?
Answer:
The height of the ball is at it's maximum 1.5 units of time after launch.
Step-by-step explanation:
Suppose we have a quadratic function in the following format:
[tex]h(t) = at^{2} + bt + c[/tex]
If t is negative, the maximu value of h(t) will happen at the point
[tex]t_{MAX} = -\frac{b}{2a}[/tex]
In this question:
[tex]h(t) = -25t^{2} + 75t + 24[/tex]
So
[tex]a = -25, b = 75, c = 24[/tex]
Then
[tex]t_{MAX} = -\frac{b}{2a} = -\frac{75}{2*(-25)} = 1.5[/tex]
The height of the ball is at it's maximum 1.5 units of time after launch.
!Please help!
When representing a frequency distribution with a bar chart, which of these bars will be the shortest?
A. A bar representing a frequency of 24
B. A bar representing a frequency of 48
C. A bar representing a frequency of 36
D. A bar representing a frequency of 12
Answer:
D
Step-by-step explanation:
12 is lowest.
A bar chart is one of the most commonly used representations or visually translate groups of data.
We have given that,
When representing a frequency distribution with a bar chart.
What is the frequency distribution?
frequency distribution, a graph or data set organized to show the frequency of occurrence of each possible outcome of a repeatable event observed many times.
It is drawn in such a way that the x-axis of the graph would represent the items and the y-axis will be for the frequency.
Out of the choices given, the shortest among the bars will be that would frequency is only 36.
Hence, the answer to this item is the letter C.
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What are the factors of 2x + 3x 54? Select two options
2x - 9
2x6
2x + 6
X-6
x+6
Answer:
(2x -9)(x +6)Step-by-step explanation:
Perhaps you're factoring ...
2x² +3x -54
= 2x² +12x -9x -54 . . . . rewrite 3x appropriately
= 2x(x +6) -9(x +6) . . . . factor pairs of terms
= (2x -9)(x +6) . . . . . . . . finish the factoring
The factors are (2x -9) and (x +6).
Please answer this correctly
4yd^2
2yd^2
6yd^2
Step-by-step explanation:
Rule: height x base/2
The area of the big triangle=2 x 4/2 = 4 yd^2
The area of the small one= 2 x2/2 =2yd^2
The total area of the trapezoid is the sum of these areas= 2+4=6yd^2
how many significant numbers in 34.6209
Answer:
6
Step-by-step explanation:
Please answer this correctly
Answer:
416
Step-by-step explanation:
plz mark brainliest!
Answer:
385
Step-by-step explanation:
use l x w
14x19
16x3
7x10
385
Suppose that weekly income of migrant workers doing agricultural labor in Florida has a distribution with a mean of $520 and a standard deviation of $90. A researcher randomly selected a sample of 100 migrant workers. What is the probability that sample mean is less than $510
Answer:
[tex] z=\frac{510-520}{\frac{90}{\sqrt{100}}}= -1.11[/tex]
And we can find the probability using the normal standard distribution table and with the complement rule we got:
[tex]P(z<-1.11)= 0.1335[/tex]
Step-by-step explanation:
For this problem we have the following parameters:
[tex] \mu = 520, \sigma = 90[/tex]
We select a sample size of n =100 and we want to find this probability:
[tex] P(\bar X <510) [/tex]
The distribution for the sample mean using the central limit theorem would be given by:
[tex]\bar X \sim N(\mu,\frac{\sigma}{\sqrt{n}})[/tex]
And we can solve this problem with the z score formula given by:
[tex] z=\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And if we find the z score formula we got:
[tex] z=\frac{510-520}{\frac{90}{\sqrt{100}}}= -1.11[/tex]
And we can find the probability using the normal standard distribution table and with the complement rule we got:
[tex]P(z<-1.11)= 0.1335[/tex]
Venera sent a chain letter to her friends, asking them to forward the letter to more friends.
The relationship between the elapsed time t, in months, since Venera sent the letter, and the number of
people, P(t), who receive the email is modeled by the following function:
3t+7
P(t) = 2
Complete the following sentence about the monthly rate of change in the number of people who receive
the email.
Round your answer to two decimal places.
Every month, the number of people who receive the email is multiplied by a factor of
Answer:
It is multiplied by a factor of 8
Step-by-step explanation:
Every month, the number of people who receive the email is multiplied by a factor of 8.
What is an exponent?Let b is the base and x is the power of the exponent function and a is the leading coefficient. The exponent is given as
y = a(b)ˣ
Venera sent a chain letter to her friends, asking them to forward the letter to more friends.
The relationship between the elapsed time t, in months, since Venera sent the letter, and the number of people, P(t), who receive the email is modeled by the following function:
[tex]\rm P(t) = 2^{3t+7}[/tex]
Every month, the number of people who receive the email is multiplied by a factor will be
For t = 2, we have
P(2) = 2³⁽²⁾⁺⁷
P(2) = 2¹³
For t = 3, we have
P(3) = 2³⁽³⁾⁺⁷
P(3) = 2¹⁶
Then the factor will be
⇒ P(3) / P(2)
⇒ 2¹⁶ / 2¹³
⇒ 2³
⇒ 8
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Which of the following best describes the slope of the line below?
PLSSS HELP
The slope is zero. Slope formula is Y=mx+b and since B is 1.5 and it is a straight line, Y=mx+1.5. What plus 1.5 is 1.5? 0. Hope this helps.
Find the area of a regular hexagon with a side length of 5cm, Round to the nearest tenth.
Answer:
i think its 64.95cm
Step-by-step explanation:
The local swim team is considering offering a new semi-private class aimed at entry-level swimmers, but needs at minimum number of swimmers to sign up in order to be cost effective. Last year's data showed that during 8 swim sessions the average number of entry-level swimmers attending was 15. Suppose the instructor wants to conduct a hypothesis test. The alternative hypothesis for this hypothesis test is: "the population mean is less than 15". The sample size is 8, LaTeX: \sigmaσ is known, and alpha =.05, the critical value of z is _______. Group of answer choices
Answer:
The signficance level is 0.05 and then based in the alternative hypothesis we can find a critical value who accumulates 0.05 of the area in the normal standard curve in the left and we got:
[tex] z_{\alpha/2}= -1.64[/tex]
Step-by-step explanation:
[tex]n=8[/tex] the same size given
[te]\sigma[/tex] the population deviation is known
For this case we want to test if the population mean is less than 15 and that represent the alternative hypothesis and the complement would be the null hypothesis. So then the system of hypothesis are:
Null hypothesis: [tex]\mu \geq 15[/tex]
Alternative hypothesis: [tex]\mu <15[/tex]
The signficance level is 0.05 and then based in the alternative hypothesis we can find a critical value who accumulates 0.05 of the area in the normal standard curve in the left and we got:
[tex] z_{\alpha/2}= -1.64[/tex]
The function h(t) = -4.92f^2 + 17.69f + 575 is used to model the height of an object being tossed from a tall building, where h(t) is the height in meters and t is the time in seconds. What are the domain and range?
Answer:
rounded to 3 decimal places ...
domain: [0, 12.757]range: [0, 590.901]Step-by-step explanation:
The function can be put into vertex form:
h(t) = -4.92(t -(1769/984))^2 +575 +4.92(1769/984)^2
h(t) ≈ -4.92(t -1.79776)^2 +590.90122
The value of h(t) is zero for ...
t = √(590.90122/4.92) +1.79776 ≈ 12.75686
For practical purposes, the domain of the function is those values of t between the time the object is tossed and the time it hits the ground. That is, the domain is ...
0 ≤ t ≤ 12.75686
The range is the set of useful vertical heights, so extends from 0 to the maximum height, given by the vertex.
The range is 0 ≤ h(t) ≤ 590.90122.
_____
Alternate interpretation of the question
The function h(t) is defined for all values of t, so that could be considered the domain.
The function h(t) only gives values less than its vertex value, so the range could be considered to extend from negative infinity to that maximum.
Which of the following best forms the figure shown
Answer:
2 rays that meet at an endpoint
Step-by-step explanation: A ray starts with a dot, or point and continues on forever with an arrow. There are two rays in that drawing that start at the same endpoint.
Answer:
2 rays that meet at an endpoint.
Step-by-step explanation:
A ray is straight but has one endpoint and the other end go on infinitely.
A line is straight and goes on infinitely.
A line segment is straight and has two endpoints.
The picture shows two rays meeting at an endpoint.
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
D. It would be less steep
Step-by-step explanation:
The first graph moves at a rate of 5/1 which is a greater fraction than 3/4
The second graph is shallow due to the close points in x and y that are able to be conducted The first Graph rapidly increases at a way higher rate making it VERY steepWhile both are linear the second strays away in terms of plot linesYou are situated 300 feet from the base of Tower Glitz Plaza watching an external elevator descend down the side of the building. At a certain instant the elevator is 500 feet away from you, and its distance from you is decreasing at a rate of 16 ft/sec. How fast is the elevator descending at that instant?
Answer:
18.66 ft/s
Step-by-step explanation:
The distance between you and the elevator is given by:
[tex]h=\sqrt{x^2+y^2}[/tex]
The rate of change for the distance between you and the elevator is given by:
[tex]\frac{dh}{dt}=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]-16=\frac{dh}{dy}*\frac{dy}{dt}[/tex]
[tex]\frac{dh}{dy}=\frac{d}{dy} (\sqrt{x^2+y^2})\\[/tex]
Applying the chain rule:
[tex]u=x^2+y^2\\\frac{dh}{dy}=\frac{d\sqrt u}{du} *\frac{du}{dy}\\\frac{dh}{dy}=\frac{1}{2\sqrt u} *2y\\\frac{dh}{dy}=\frac{y}{\sqrt {(x^2+y^2)}}[/tex]
Therefore, at x=300 and y = 500, dy/dt is:
[tex]-16=\frac{y}{\sqrt {(x^2+y^2)}}*\frac{dy}{dt}\\-16=\frac{500}{\sqrt {(300^2+500^2)}}*\frac{dy}{dt}\\\frac{dy}{dt}=-18.66\ ft/s[/tex]
The elevator is descending at 18.66 ft/s.
