Answer:
A. 0.62%
B. 28 months
Step-by-step explanation:
A. Calculation for what percentage of total production will the company expect to replace
Let x represents the distribution of life times
Let mean be 34 months
Let standard deviation be 4 months.
Based on the information the full refund on any defective watch for 2 years will represent 24 months (2 years *12 months).
First step
P(X<24)
= p(x-mean/ standard deviation< 24-34/4)
= p(z< -10/4)
=P(z<-2.5)
Second step is to Use the excel function to find NORMSDIST(z) of P(z<-2.5)
NORMSDIST(z)=0.62%
Therefore the percentage of total production will the company expect to replace will be 0.62%
B. Calculation for how much the guarantee period should be
First step
P(X<x)=0.06
P(x-Mean/Standard deviation < x-34/4) = 0.06
Second Step is to Use excel function
P(z<x-34/4) = (Normsinv(0.06)
x-34/4 = -1.555
Now let calculate how much the guarantee period should be
x = -6.22+34 months
x = 27.78
x = 28 months (Approximately)
Therefore the guarantee period should be 28 months
make a plotting graph and use the x and y axis and make little point :) hope this helps
Answer: (6,-2)
Step-by-step explanation:
i hope this helps
Answer:
The standard deviation of the age distribution is 6.2899 years.
Step-by-step explanation:
The formula to compute the standard deviation is:

The data provided is:
X = {19, 19, 21, 25, 25, 28, 29, 30, 31, 32, 40}
Compute the mean of the data as follows:

![=\frac{1}{11}\times [19+19+21+...+40]\\\\=\frac{299}{11}\\\\=27.182](https://tex.z-dn.net/?f=%3D%5Cfrac%7B1%7D%7B11%7D%5Ctimes%20%5B19%2B19%2B21%2B...%2B40%5D%5C%5C%5C%5C%3D%5Cfrac%7B299%7D%7B11%7D%5C%5C%5C%5C%3D27.182)
Compute the standard deviation as follows:

![=\sqrt{\frac{1}{11-1}\times [(19-27.182)^{2}+(19-27.182)^{2}+...+(40-27.182)^{2}]}}\\\\=\sqrt{\frac{395.6364}{10}}\\\\=6.28996\\\\\approx 6.2899](https://tex.z-dn.net/?f=%3D%5Csqrt%7B%5Cfrac%7B1%7D%7B11-1%7D%5Ctimes%20%5B%2819-27.182%29%5E%7B2%7D%2B%2819-27.182%29%5E%7B2%7D%2B...%2B%2840-27.182%29%5E%7B2%7D%5D%7D%7D%5C%5C%5C%5C%3D%5Csqrt%7B%5Cfrac%7B395.6364%7D%7B10%7D%7D%5C%5C%5C%5C%3D6.28996%5C%5C%5C%5C%5Capprox%206.2899)
Thus, the standard deviation of the age distribution is 6.2899 years.