Answer:
a) 0.1353
b) 0.3679
Step-by-step explanation:
Let's start by defining the random variable T.
T : ''The time (in hours) required to repair a machine''
T ~ exp (λ)
T ~ exp (1)
The probability density function for the exponential distribution is
(In the equation I replaced λ = L)
With L > 0 and x ≥ 0
In this exercise λ = 1 ⇒
For a)
For b)
The event (T ≥ 10 / T > 9) is equivalent to the event T ≥ 1 so they have the same probability of occur
Answer:
65.45
Step-by-step explanation:
Zscore = (x - mean) / standard deviation
x = score
Percentage below C :
D = 18% ; F = 12%
Sum = 30%
Obtain the Zscore for the proportion below D
P(Z < 0.30) = -0.524
Hence, Zscore = -0.524
Put Zscore = -0.524 in the equation :
-0.524 = (x - 72) / 12.5
-0.524 * 12.5 = x - 72
-6.55 = x - 72
-6.55 + 72 = x
x = 65.45
To receive a grade of C or better, score must be atleast 65.45
well, we're assuming all along that Merina owes Bradford $2000, because in the 1st scenario, she was going to pay twice $1000.
on the 2nd scenario, she'll be paying the same $2000 but split 7 months from now and then 7 months later, same 2000 bucks, at which point Bradford applied 8.5% interest.
using those assumptions, since the wording is not quite clear, we can say that Merina is simply paying 2000 bucks plus the 8.5%
![\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{8.5\% of 2000}}{\left( \cfrac{8.5}{100} \right)2000}\implies 170 \\\\[-0.35em] ~\dotfill\\\\ \cfrac{\stackrel{principal}{2000}~~ + ~~\stackrel{interest}{170}}{2}\implies \stackrel{\textit{two equal payments of}}{1085}](https://tex.z-dn.net/?f=%5Cbegin%7Barray%7D%7B%7Cc%7Cll%7D%20%5Ccline%7B1-1%7D%20%5Ctextit%7Ba%5C%25%20of%20b%7D%5C%5C%20%5Ccline%7B1-1%7D%20%5C%5C%20%5Cleft%28%20%5Ccfrac%7Ba%7D%7B100%7D%20%5Cright%29%5Ccdot%20b%20%5C%5C%5C%5C%20%5Ccline%7B1-1%7D%20%5Cend%7Barray%7D~%5Chspace%7B5em%7D%5Cstackrel%7B%5Ctextit%7B8.5%5C%25%20of%202000%7D%7D%7B%5Cleft%28%20%5Ccfrac%7B8.5%7D%7B100%7D%20%5Cright%292000%7D%5Cimplies%20170%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Ccfrac%7B%5Cstackrel%7Bprincipal%7D%7B2000%7D~~%20%2B%20~~%5Cstackrel%7Binterest%7D%7B170%7D%7D%7B2%7D%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Btwo%20equal%20payments%20of%7D%7D%7B1085%7D)
The function of the length z in meters of the side parallel to the wall is A(z) = z/2(210 - z)
<h3>How to write a function of the length z in meters of the side parallel to the wall?</h3>
The given parameters are:
Perimeter = 210 meters
Let the length parallel to the wall be represented as z and the width be x
So, the perimeter of the fence is
P = 2x + z
This gives
210 = 2x + z
Make x the subject
x = 1/2(210 - z)
The area of the wall is calculated as
A = xz
So, we have
A = 1/2(210 - z) * z
This gives
A = z/2(210 - z)
Rewrite as
A(z) = z/2(210 - z)
Hence, the function of the length z in meters of the side parallel to the wall is A(z) = z/2(210 - z)
Read more about functions at
brainly.com/question/1415456
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