Answer:
Step-by-step explanation:
Hello!
You need to construct a 95% CI for the population mean of the length of engineering conferences.
The variable has a normal distribution.
The information given is:
n= 84
x[bar]= 3.94
δ= 1.28
The formula for the Confidence interval is:
x[bar]±
*(δ/n)
Lower bound(Lb): 3.698
Upper bound(Ub): 4.182
Error bound: (Ub - Lb)/2 = (4.182-3.698)/2 = 0.242
I hope it helps!
(7,5)(-4,-1)
slope = (-1-5) / (-4-7) = -6/-11 = 6/11
y - y1 = m(x - x1)
slope(m) = 6/11
(-4,-1)...x1 = -4 and y1 = -1
now we sub...pay close attention to ur signs
y - (-1) = 6/11(x - (-4) ...not done yet...
y + 1 = 6/11(x + 4) <===
I got 1.5, but I could be wrong.
Since you mentioned calculus, perhaps you're supposed to find the area by integration.
The square is circumscribed by a circle of radius 6, so its diagonal (equal to the diameter) has length 12. The lengths of a square's side and its diagonal occur in a ratio of 1 to sqrt(2), so the square has side length 6sqrt(2). This means its sides occur on the lines
and
.
Let
be the region bounded by the line
and the circle
(the rightmost blue region). The right side of the circle can be expressed in terms of
as a function of
:

Then the area of this circular segment is


Substitute
, so that 


Then the area of the entire blue region is 4 times this, a total of
.
Alternatively, you can compute the area of
in polar coordinates. The line
becomes
, while the circle is given by
. The two curves intersect at
, so that


so again the total area would be
.
Or you can omit using calculus altogether and rely on some basic geometric facts. The region
is a circular segment subtended by a central angle of
radians. Then its area is

so the total area is, once again,
.
An even simpler way is to subtract the area of the square from the area of the circle.

a) Remember that the y-intercept of a exponential function

is

, so the only thing to do to find the y-intercept in our functions is evaluate it at t=0:




We can conclude that the y-intercept of our function is (0,50), and it represents the initial bacteria population in the sample.
b) To find if the function is growing or decaying, we are going to convert its decimal part to a fraction. Then, we will compare the numerator and the denominator of the fraction. If the numerator is grater than the denominator, the function is growing; if the opposite is true, the function is decaying.
Remember that to convert a decimal into a fraction we are going to add the denominator 1 to our decimal and then we'll multiply both of them by a power of ten for each number after the decimal point:

Now we can rewrite our exponential function:

Since the numerator is grater than the denominator, it is growing faster than the denominator; therefore the function is growing.
c) The only thing we need to do here is evaluate the function at t=5:




We can conclude that after 5 hours <span>Dr. Silas began her study will be 268.9 bacteria in the sample.</span>