Answer:
Step-by-step explanation:
Distribute: 6(4-z) expands to 24-6z
24-6z=2z: Add 6z to both sides to get 24=8z
Divide both sides by 8: z=3
Answer:
Explanation:
Let x be the age of the person who enter the room
(18 + 25 + 18 + 21 + 16 + x)/6 = 25
(77 + x)/6 = 25
77 + x = 25(6)
77 + x = 150
x = 150 - 77
x = 73
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
The explicit formula for a arithmetic sequence is a_n = a_1 + (n - 1)d.
We want to find a_21.
a_21 = 17 + (21 - 1)(10)
a_21 = 17 + (20)(10)
a_21 = 17 + 200
a_21 = 217
The 21st term is 217.
