Answer:
(x-8)/10
Step-by-step explanation:
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Answer:
a)= 2
b) 6.324
c) P= 0.1217
Step-by-step explanation:
a) The mean of the sampling distribution of X`1- X`2 denoted by ux`-x` = u1-u2 is equal to the difference between population means i.e = 2 ( given in the question)
b) The standard deviation of the sampling distribution of X`1- X`2 ( standard error of X`1- X`2) denoted by σ_X`1- X`2 is given by
σ_X`1- X`2 = √σ²/n1 +σ²/n2
Var ( X`1- X`2) = Var X`1 + Var X`2 = σ²/n1 +σ²/n2
so
σ_X`1- X`2 =√20 +20 = 6.324
if the populations are normal the sampling distribution X`1- X`2 , regardless of sample sizes , will be normal with mean u1-u2 and variance σ²/n1 +σ²/n2.
Where as Z is normally distributed with mean zero and unit variance.
If we take X`1- X`2= 0 and u1-u2= 2 and standard deviation of the sampling distribution = 6.324 then
Z= 0-2/ 6.342= -0.31625
P(-0.31625<z<0)= 0.1217
The probability would be 0.1217
Answer:
13 trails
Step-by-step explanation:
The histogram shows following numbers of trails:
- <u>0 - 6 km long</u> - 5 trails;
- 6 - 12 km long - 9 trails;
- 12 - 18 km long - 7 trails;
- 18 - 24 km long - 3 trails;
- <u>24 - 30 km long</u> - 4 trails;
- <u>30 - 36 km long</u> - 1 trail;
- <u>36 - 42 km long</u> - 3 trails.
So, there are 5 trails with length less than 6 km and 4 + 1 + 3 = 8 trails that are at least 24 km long.
In total, 5 + 8 = 13 trails
Answer:
11 ways
Step-by-step explanation:
10 crunchy
9 crunchy 1 crispy
8 crunchy 2 crispy
7 crunchy 3 crispy
6 crunchy 4 crispy
5 crunchy 5 crispy
4 crunchy 6 crispy
3 crunchy 7 crispy
2 crunchy 8 crispy
1 crunchy 9 crispy
10 crispy
Answer:
2x² + 15x + 27
Step-by-step explanation:
(2x + 9)(x+3)
2x² + 6x + 9x+ 27
2x² + 15x + 27