Answer:
A normal distribution or z-test is used to construct a confidence interval.
Step-by-step explanation:
We are given the following in the question:
Sample mean,
= $3120
Sample size, n = 40
Population standard deviation, σ = $677
The distribution of earnings of college is a normal distribution.
Conditions:
- Since we are given the population standard deviation and the the sample size is also greater than 30.
Conclusion:
Thus, we use a normal distribution or z-test to construct a confidence interval.
Answer:
Part A)
x=-3i
x=3i
Part B)
(x+3i)(x-3i)
Step-by-step explanation:
Given:
Part A)
x^2+9=0
x^2=-9
x= √-9
x=√-1 *√9
x=± i *3
x=±3i
Part B)
x^2+9=0
x^2 - (-9)=0
x2-(3i)^2=0
(x-3i)(x+3i)=0 !
The nails less than 2 inches long are the ones that are 1/2”, 1”, and 1 1/2”, if I am reading the table correctly.
4 x 1/2” = 2”
2 x 1” = 2”
2 x 1 1/2” = 3”
2 + 2 + 3 = 7 inches
Answer:
It's 3 x 10 1
Step-by-step explanation:
:)