Answer: a) 0.84 b) 0.67 c) 1.28
Step-by-step explanation:
Using the standard normal distribution table for z-value , we have
(a) The value of
would result in a 80% one-sided confidence interval : 
(b) The value of
would result in a 85% one-sided confidence interval : 
(c) The value of
would result in a 90% one-sided confidence interval : 
There are two ways to work this out: normal variables or using "imaginary" numbers.
Normal variables:
![(7+2i)(3-i)\\(7*3)+[7*(-i)]+(3*2i)+[2i*(-i)]\\21-7i+6i-2i^{2}\\\\21-i-2i^{2}](https://tex.z-dn.net/?f=%20%287%2B2i%29%283-i%29%5C%5C%287%2A3%29%2B%5B7%2A%28-i%29%5D%2B%283%2A2i%29%2B%5B2i%2A%28-i%29%5D%5C%5C21-7i%2B6i-2i%5E%7B2%7D%5C%5C%5C%5C21-i-2i%5E%7B2%7D)
Imaginary numbers:
Using the result from earlier:

Now since

, then the expression becomes:
B is dilated by a factor of 5
Answer:
x = 11
Step-by-step explanation:
(x+5)2 = 32
2x + 10 = 32
2x = 32 - 10
2x = 22
x = 11
1/2* N= 1/3
⇒ N= (1/3)/ (1/2)
⇒ N= (1/3)* (2/1)
⇒ N= 2/3
The final answer is N= 2/3~